--- /dev/null
+ module minimm
+!-----------------------------------------------------------------------------
+ use io_units
+ use names
+ use math
+! use MPI_data
+ use geometry_data
+ use energy_data
+ use control_data
+ use minim_data
+ use geometry
+! use csa_data
+! use energy
+ implicit none
+!-----------------------------------------------------------------------------
+!
+!
+!-----------------------------------------------------------------------------
+ contains
+!-----------------------------------------------------------------------------
+! cored.f
+!-----------------------------------------------------------------------------
+ subroutine assst(iv, liv, lv, v)
+!
+! *** assess candidate step (***sol version 2.3) ***
+!
+ integer :: liv, l,lv
+ integer :: iv(liv)
+ real(kind=8) :: v(lv)
+!
+! *** purpose ***
+!
+! this subroutine is called by an unconstrained minimization
+! routine to assess the next candidate step. it may recommend one
+! of several courses of action, such as accepting the step, recom-
+! puting it using the same or a new quadratic model, or halting due
+! to convergence or false convergence. see the return code listing
+! below.
+!
+!-------------------------- parameter usage --------------------------
+!
+! iv (i/o) integer parameter and scratch vector -- see description
+! below of iv values referenced.
+! liv (in) length of iv array.
+! lv (in) length of v array.
+! v (i/o) real parameter and scratch vector -- see description
+! below of v values referenced.
+!
+! *** iv values referenced ***
+!
+! iv(irc) (i/o) on input for the first step tried in a new iteration,
+! iv(irc) should be set to 3 or 4 (the value to which it is
+! set when step is definitely to be accepted). on input
+! after step has been recomputed, iv(irc) should be
+! unchanged since the previous return of assst.
+! on output, iv(irc) is a return code having one of the
+! following values...
+! 1 = switch models or try smaller step.
+! 2 = switch models or accept step.
+! 3 = accept step and determine v(radfac) by gradient
+! tests.
+! 4 = accept step, v(radfac) has been determined.
+! 5 = recompute step (using the same model).
+! 6 = recompute step with radius = v(lmaxs) but do not
+! evaulate the objective function.
+! 7 = x-convergence (see v(xctol)).
+! 8 = relative function convergence (see v(rfctol)).
+! 9 = both x- and relative function convergence.
+! 10 = absolute function convergence (see v(afctol)).
+! 11 = singular convergence (see v(lmaxs)).
+! 12 = false convergence (see v(xftol)).
+! 13 = iv(irc) was out of range on input.
+! return code i has precdence over i+1 for i = 9, 10, 11.
+! iv(mlstgd) (i/o) saved value of iv(model).
+! iv(model) (i/o) on input, iv(model) should be an integer identifying
+! the current quadratic model of the objective function.
+! if a previous step yielded a better function reduction,
+! then iv(model) will be set to iv(mlstgd) on output.
+! iv(nfcall) (in) invocation count for the objective function.
+! iv(nfgcal) (i/o) value of iv(nfcall) at step that gave the biggest
+! function reduction this iteration. iv(nfgcal) remains
+! unchanged until a function reduction is obtained.
+! iv(radinc) (i/o) the number of radius increases (or minus the number
+! of decreases) so far this iteration.
+! iv(restor) (out) set to 1 if v(f) has been restored and x should be
+! restored to its initial value, to 2 if x should be saved,
+! to 3 if x should be restored from the saved value, and to
+! 0 otherwise.
+! iv(stage) (i/o) count of the number of models tried so far in the
+! current iteration.
+! iv(stglim) (in) maximum number of models to consider.
+! iv(switch) (out) set to 0 unless a new model is being tried and it
+! gives a smaller function value than the previous model,
+! in which case assst sets iv(switch) = 1.
+! iv(toobig) (in) is nonzero if step was too big (e.g. if it caused
+! overflow).
+! iv(xirc) (i/o) value that iv(irc) would have in the absence of
+! convergence, false convergence, and oversized steps.
+!
+! *** v values referenced ***
+!
+! v(afctol) (in) absolute function convergence tolerance. if the
+! absolute value of the current function value v(f) is less
+! than v(afctol), then assst returns with iv(irc) = 10.
+! v(decfac) (in) factor by which to decrease radius when iv(toobig) is
+! nonzero.
+! v(dstnrm) (in) the 2-norm of d*step.
+! v(dstsav) (i/o) value of v(dstnrm) on saved step.
+! v(dst0) (in) the 2-norm of d times the newton step (when defined,
+! i.e., for v(nreduc) .ge. 0).
+! v(f) (i/o) on both input and output, v(f) is the objective func-
+! tion value at x. if x is restored to a previous value,
+! then v(f) is restored to the corresponding value.
+! v(fdif) (out) the function reduction v(f0) - v(f) (for the output
+! value of v(f) if an earlier step gave a bigger function
+! decrease, and for the input value of v(f) otherwise).
+! v(flstgd) (i/o) saved value of v(f).
+! v(f0) (in) objective function value at start of iteration.
+! v(gtslst) (i/o) value of v(gtstep) on saved step.
+! v(gtstep) (in) inner product between step and gradient.
+! v(incfac) (in) minimum factor by which to increase radius.
+! v(lmaxs) (in) maximum reasonable step size (and initial step bound).
+! if the actual function decrease is no more than twice
+! what was predicted, if a return with iv(irc) = 7, 8, 9,
+! or 10 does not occur, if v(dstnrm) .gt. v(lmaxs), and if
+! v(preduc) .le. v(sctol) * abs(v(f0)), then assst re-
+! turns with iv(irc) = 11. if so doing appears worthwhile,
+! then assst repeats this test with v(preduc) computed for
+! a step of length v(lmaxs) (by a return with iv(irc) = 6).
+! v(nreduc) (i/o) function reduction predicted by quadratic model for
+! newton step. if assst is called with iv(irc) = 6, i.e.,
+! if v(preduc) has been computed with radius = v(lmaxs) for
+! use in the singular convervence test, then v(nreduc) is
+! set to -v(preduc) before the latter is restored.
+! v(plstgd) (i/o) value of v(preduc) on saved step.
+! v(preduc) (i/o) function reduction predicted by quadratic model for
+! current step.
+! v(radfac) (out) factor to be used in determining the new radius,
+! which should be v(radfac)*dst, where dst is either the
+! output value of v(dstnrm) or the 2-norm of
+! diag(newd)*step for the output value of step and the
+! updated version, newd, of the scale vector d. for
+! iv(irc) = 3, v(radfac) = 1.0 is returned.
+! v(rdfcmn) (in) minimum value for v(radfac) in terms of the input
+! value of v(dstnrm) -- suggested value = 0.1.
+! v(rdfcmx) (in) maximum value for v(radfac) -- suggested value = 4.0.
+! v(reldx) (in) scaled relative change in x caused by step, computed
+! (e.g.) by function reldst as
+! max (d(i)*abs(x(i)-x0(i)), 1 .le. i .le. p) /
+! max (d(i)*(abs(x(i))+abs(x0(i))), 1 .le. i .le. p).
+! v(rfctol) (in) relative function convergence tolerance. if the
+! actual function reduction is at most twice what was pre-
+! dicted and v(nreduc) .le. v(rfctol)*abs(v(f0)), then
+! assst returns with iv(irc) = 8 or 9.
+! v(stppar) (in) marquardt parameter -- 0 means full newton step.
+! v(tuner1) (in) tuning constant used to decide if the function
+! reduction was much less than expected. suggested
+! value = 0.1.
+! v(tuner2) (in) tuning constant used to decide if the function
+! reduction was large enough to accept step. suggested
+! value = 10**-4.
+! v(tuner3) (in) tuning constant used to decide if the radius
+! should be increased. suggested value = 0.75.
+! v(xctol) (in) x-convergence criterion. if step is a newton step
+! (v(stppar) = 0) having v(reldx) .le. v(xctol) and giving
+! at most twice the predicted function decrease, then
+! assst returns iv(irc) = 7 or 9.
+! v(xftol) (in) false convergence tolerance. if step gave no or only
+! a small function decrease and v(reldx) .le. v(xftol),
+! then assst returns with iv(irc) = 12.
+!
+!------------------------------- notes -------------------------------
+!
+! *** application and usage restrictions ***
+!
+! this routine is called as part of the nl2sol (nonlinear
+! least-squares) package. it may be used in any unconstrained
+! minimization solver that uses dogleg, goldfeld-quandt-trotter,
+! or levenberg-marquardt steps.
+!
+! *** algorithm notes ***
+!
+! see (1) for further discussion of the assessing and model
+! switching strategies. while nl2sol considers only two models,
+! assst is designed to handle any number of models.
+!
+! *** usage notes ***
+!
+! on the first call of an iteration, only the i/o variables
+! step, x, iv(irc), iv(model), v(f), v(dstnrm), v(gtstep), and
+! v(preduc) need have been initialized. between calls, no i/o
+! values execpt step, x, iv(model), v(f) and the stopping toler-
+! ances should be changed.
+! after a return for convergence or false convergence, one can
+! change the stopping tolerances and call assst again, in which
+! case the stopping tests will be repeated.
+!
+! *** references ***
+!
+! (1) dennis, j.e., jr., gay, d.m., and welsch, r.e. (1981),
+! an adaptive nonlinear least-squares algorithm,
+! acm trans. math. software, vol. 7, no. 3.
+!
+! (2) powell, m.j.d. (1970) a fortran subroutine for solving
+! systems of nonlinear algebraic equations, in numerical
+! methods for nonlinear algebraic equations, edited by
+! p. rabinowitz, gordon and breach, london.
+!
+! *** history ***
+!
+! john dennis designed much of this routine, starting with
+! ideas in (2). roy welsch suggested the model switching strategy.
+! david gay and stephen peters cast this subroutine into a more
+! portable form (winter 1977), and david gay cast it into its
+! present form (fall 1978).
+!
+! *** general ***
+!
+! this subroutine was written in connection with research
+! supported by the national science foundation under grants
+! mcs-7600324, dcr75-10143, 76-14311dss, mcs76-11989, and
+! mcs-7906671.
+!
+!------------------------ external quantities ------------------------
+!
+! *** no external functions and subroutines ***
+!
+! *** intrinsic functions ***
+!/+
+!el real(kind=8) :: dabs, dmax1
+!/
+! *** no common blocks ***
+!
+!-------------------------- local variables --------------------------
+!
+ logical :: goodx
+ integer :: i, nfc
+ real(kind=8) :: emax, emaxs, gts, rfac1, xmax
+!el real(kind=8) :: half, one, onep2, two, zero
+!
+! *** subscripts for iv and v ***
+!
+!el integer :: afctol, decfac, dstnrm, dstsav, dst0, f, fdif, flstgd, f0,&
+!el gtslst, gtstep, incfac, irc, lmaxs, mlstgd, model, nfcall,&
+!el nfgcal, nreduc, plstgd, preduc, radfac, radinc, rdfcmn,&
+!el rdfcmx, reldx, restor, rfctol, sctol, stage, stglim,&
+!el stppar, switch, toobig, tuner1, tuner2, tuner3, xctol,&
+!el xftol, xirc
+!
+!
+! *** data initializations ***
+!
+!/6
+! data half/0.5d+0/, one/1.d+0/, onep2/1.2d+0/, two/2.d+0/,
+! 1 zero/0.d+0/
+!/7
+ real(kind=8),parameter :: half=0.5d+0, one=1.d+0, onep2=1.2d+0, two=2.d+0,&
+ zero=0.d+0
+!/
+!
+!/6
+! data irc/29/, mlstgd/32/, model/5/, nfcall/6/, nfgcal/7/,
+! 1 radinc/8/, restor/9/, stage/10/, stglim/11/, switch/12/,
+! 2 toobig/2/, xirc/13/
+!/7
+ integer,parameter :: irc=29, mlstgd=32, model=5, nfcall=6, nfgcal=7,&
+ radinc=8, restor=9, stage=10, stglim=11, switch=12,&
+ toobig=2, xirc=13
+!/
+!/6
+! data afctol/31/, decfac/22/, dstnrm/2/, dst0/3/, dstsav/18/,
+! 1 f/10/, fdif/11/, flstgd/12/, f0/13/, gtslst/14/, gtstep/4/,
+! 2 incfac/23/, lmaxs/36/, nreduc/6/, plstgd/15/, preduc/7/,
+! 3 radfac/16/, rdfcmn/24/, rdfcmx/25/, reldx/17/, rfctol/32/,
+! 4 sctol/37/, stppar/5/, tuner1/26/, tuner2/27/, tuner3/28/,
+! 5 xctol/33/, xftol/34/
+!/7
+ integer,parameter :: afctol=31, decfac=22, dstnrm=2, dst0=3, dstsav=18,&
+ f=10, fdif=11, flstgd=12, f0=13, gtslst=14, gtstep=4,&
+ incfac=23, lmaxs=36, nreduc=6, plstgd=15, preduc=7,&
+ radfac=16, rdfcmn=24, rdfcmx=25, reldx=17, rfctol=32,&
+ sctol=37, stppar=5, tuner1=26, tuner2=27, tuner3=28,&
+ xctol=33, xftol=34
+!/
+!
+!+++++++++++++++++++++++++++++++ body ++++++++++++++++++++++++++++++++
+!
+ nfc = iv(nfcall)
+ iv(switch) = 0
+ iv(restor) = 0
+ rfac1 = one
+ goodx = .true.
+ i = iv(irc)
+ if (i .ge. 1 .and. i .le. 12) &
+ go to (20,30,10,10,40,280,220,220,220,220,220,170), i
+ iv(irc) = 13
+ go to 999
+!
+! *** initialize for new iteration ***
+!
+ 10 iv(stage) = 1
+ iv(radinc) = 0
+ v(flstgd) = v(f0)
+ if (iv(toobig) .eq. 0) go to 110
+ iv(stage) = -1
+ iv(xirc) = i
+ go to 60
+!
+! *** step was recomputed with new model or smaller radius ***
+! *** first decide which ***
+!
+ 20 if (iv(model) .ne. iv(mlstgd)) go to 30
+! *** old model retained, smaller radius tried ***
+! *** do not consider any more new models this iteration ***
+ iv(stage) = iv(stglim)
+ iv(radinc) = -1
+ go to 110
+!
+! *** a new model is being tried. decide whether to keep it. ***
+!
+ 30 iv(stage) = iv(stage) + 1
+!
+! *** now we add the possibiltiy that step was recomputed with ***
+! *** the same model, perhaps because of an oversized step. ***
+!
+ 40 if (iv(stage) .gt. 0) go to 50
+!
+! *** step was recomputed because it was too big. ***
+!
+ if (iv(toobig) .ne. 0) go to 60
+!
+! *** restore iv(stage) and pick up where we left off. ***
+!
+ iv(stage) = -iv(stage)
+ i = iv(xirc)
+ go to (20, 30, 110, 110, 70), i
+!
+ 50 if (iv(toobig) .eq. 0) go to 70
+!
+! *** handle oversize step ***
+!
+ if (iv(radinc) .gt. 0) go to 80
+ iv(stage) = -iv(stage)
+ iv(xirc) = iv(irc)
+!
+ 60 v(radfac) = v(decfac)
+ iv(radinc) = iv(radinc) - 1
+ iv(irc) = 5
+ iv(restor) = 1
+ go to 999
+!
+ 70 if (v(f) .lt. v(flstgd)) go to 110
+!
+! *** the new step is a loser. restore old model. ***
+!
+ if (iv(model) .eq. iv(mlstgd)) go to 80
+ iv(model) = iv(mlstgd)
+ iv(switch) = 1
+!
+! *** restore step, etc. only if a previous step decreased v(f).
+!
+ 80 if (v(flstgd) .ge. v(f0)) go to 110
+ iv(restor) = 1
+ v(f) = v(flstgd)
+ v(preduc) = v(plstgd)
+ v(gtstep) = v(gtslst)
+ if (iv(switch) .eq. 0) rfac1 = v(dstnrm) / v(dstsav)
+ v(dstnrm) = v(dstsav)
+ nfc = iv(nfgcal)
+ goodx = .false.
+!
+ 110 v(fdif) = v(f0) - v(f)
+ if (v(fdif) .gt. v(tuner2) * v(preduc)) go to 140
+ if(iv(radinc).gt.0) go to 140
+!
+! *** no (or only a trivial) function decrease
+! *** -- so try new model or smaller radius
+!
+ if (v(f) .lt. v(f0)) go to 120
+ iv(mlstgd) = iv(model)
+ v(flstgd) = v(f)
+ v(f) = v(f0)
+ iv(restor) = 1
+ go to 130
+ 120 iv(nfgcal) = nfc
+ 130 iv(irc) = 1
+ if (iv(stage) .lt. iv(stglim)) go to 160
+ iv(irc) = 5
+ iv(radinc) = iv(radinc) - 1
+ go to 160
+!
+! *** nontrivial function decrease achieved ***
+!
+ 140 iv(nfgcal) = nfc
+ rfac1 = one
+ v(dstsav) = v(dstnrm)
+ if (v(fdif) .gt. v(preduc)*v(tuner1)) go to 190
+!
+! *** decrease was much less than predicted -- either change models
+! *** or accept step with decreased radius.
+!
+ if (iv(stage) .ge. iv(stglim)) go to 150
+! *** consider switching models ***
+ iv(irc) = 2
+ go to 160
+!
+! *** accept step with decreased radius ***
+!
+ 150 iv(irc) = 4
+!
+! *** set v(radfac) to fletcher*s decrease factor ***
+!
+ 160 iv(xirc) = iv(irc)
+ emax = v(gtstep) + v(fdif)
+ v(radfac) = half * rfac1
+ if (emax .lt. v(gtstep)) v(radfac) = rfac1 * dmax1(v(rdfcmn),&
+ half * v(gtstep)/emax)
+!
+! *** do false convergence test ***
+!
+ 170 if (v(reldx) .le. v(xftol)) go to 180
+ iv(irc) = iv(xirc)
+ if (v(f) .lt. v(f0)) go to 200
+ go to 230
+!
+ 180 iv(irc) = 12
+ go to 240
+!
+! *** handle good function decrease ***
+!
+ 190 if (v(fdif) .lt. (-v(tuner3) * v(gtstep))) go to 210
+!
+! *** increasing radius looks worthwhile. see if we just
+! *** recomputed step with a decreased radius or restored step
+! *** after recomputing it with a larger radius.
+!
+ if (iv(radinc) .lt. 0) go to 210
+ if (iv(restor) .eq. 1) go to 210
+!
+! *** we did not. try a longer step unless this was a newton
+! *** step.
+
+ v(radfac) = v(rdfcmx)
+ gts = v(gtstep)
+ if (v(fdif) .lt. (half/v(radfac) - one) * gts) &
+ v(radfac) = dmax1(v(incfac), half*gts/(gts + v(fdif)))
+ iv(irc) = 4
+ if (v(stppar) .eq. zero) go to 230
+ if (v(dst0) .ge. zero .and. (v(dst0) .lt. two*v(dstnrm) &
+ .or. v(nreduc) .lt. onep2*v(fdif))) go to 230
+! *** step was not a newton step. recompute it with
+! *** a larger radius.
+ iv(irc) = 5
+ iv(radinc) = iv(radinc) + 1
+!
+! *** save values corresponding to good step ***
+!
+ 200 v(flstgd) = v(f)
+ iv(mlstgd) = iv(model)
+ if (iv(restor) .ne. 1) iv(restor) = 2
+ v(dstsav) = v(dstnrm)
+ iv(nfgcal) = nfc
+ v(plstgd) = v(preduc)
+ v(gtslst) = v(gtstep)
+ go to 230
+!
+! *** accept step with radius unchanged ***
+!
+ 210 v(radfac) = one
+ iv(irc) = 3
+ go to 230
+!
+! *** come here for a restart after convergence ***
+!
+ 220 iv(irc) = iv(xirc)
+ if (v(dstsav) .ge. zero) go to 240
+ iv(irc) = 12
+ go to 240
+!
+! *** perform convergence tests ***
+!
+ 230 iv(xirc) = iv(irc)
+ 240 if (iv(restor) .eq. 1 .and. v(flstgd) .lt. v(f0)) iv(restor) = 3
+ if (half * v(fdif) .gt. v(preduc)) go to 999
+ emax = v(rfctol) * dabs(v(f0))
+ emaxs = v(sctol) * dabs(v(f0))
+ if (v(dstnrm) .gt. v(lmaxs) .and. v(preduc) .le. emaxs) &
+ iv(irc) = 11
+ if (v(dst0) .lt. zero) go to 250
+ i = 0
+ if ((v(nreduc) .gt. zero .and. v(nreduc) .le. emax) .or. &
+ (v(nreduc) .eq. zero .and. v(preduc) .eq. zero)) i = 2
+ if (v(stppar) .eq. zero .and. v(reldx) .le. v(xctol) &
+ .and. goodx) i = i + 1
+ if (i .gt. 0) iv(irc) = i + 6
+!
+! *** consider recomputing step of length v(lmaxs) for singular
+! *** convergence test.
+!
+ 250 if (iv(irc) .gt. 5 .and. iv(irc) .ne. 12) go to 999
+ if (v(dstnrm) .gt. v(lmaxs)) go to 260
+ if (v(preduc) .ge. emaxs) go to 999
+ if (v(dst0) .le. zero) go to 270
+ if (half * v(dst0) .le. v(lmaxs)) go to 999
+ go to 270
+ 260 if (half * v(dstnrm) .le. v(lmaxs)) go to 999
+ xmax = v(lmaxs) / v(dstnrm)
+ if (xmax * (two - xmax) * v(preduc) .ge. emaxs) go to 999
+ 270 if (v(nreduc) .lt. zero) go to 290
+!
+! *** recompute v(preduc) for use in singular convergence test ***
+!
+ v(gtslst) = v(gtstep)
+ v(dstsav) = v(dstnrm)
+ if (iv(irc) .eq. 12) v(dstsav) = -v(dstsav)
+ v(plstgd) = v(preduc)
+ i = iv(restor)
+ iv(restor) = 2
+ if (i .eq. 3) iv(restor) = 0
+ iv(irc) = 6
+ go to 999
+!
+! *** perform singular convergence test with recomputed v(preduc) ***
+!
+ 280 v(gtstep) = v(gtslst)
+ v(dstnrm) = dabs(v(dstsav))
+ iv(irc) = iv(xirc)
+ if (v(dstsav) .le. zero) iv(irc) = 12
+ v(nreduc) = -v(preduc)
+ v(preduc) = v(plstgd)
+ iv(restor) = 3
+ 290 if (-v(nreduc) .le. v(sctol) * dabs(v(f0))) iv(irc) = 11
+!
+ 999 return
+!
+! *** last card of assst follows ***
+ end subroutine assst
+!-----------------------------------------------------------------------------
+ subroutine deflt(alg, iv, liv, lv, v)
+!
+! *** supply ***sol (version 2.3) default values to iv and v ***
+!
+! *** alg = 1 means regression constants.
+! *** alg = 2 means general unconstrained optimization constants.
+!
+ integer :: liv, l,lv
+ integer :: alg, iv(liv)
+ real(kind=8) :: v(lv)
+!
+!el external imdcon, vdflt
+!el integer imdcon
+! imdcon... returns machine-dependent integer constants.
+! vdflt.... provides default values to v.
+!
+ integer :: miv, m
+ integer :: miniv(2), minv(2)
+!
+! *** subscripts for iv ***
+!
+!el integer algsav, covprt, covreq, dtype, hc, ierr, inith, inits,
+!el 1 ipivot, ivneed, lastiv, lastv, lmat, mxfcal, mxiter,
+!el 2 nfcov, ngcov, nvdflt, outlev, parprt, parsav, perm,
+!el 3 prunit, qrtyp, rdreq, rmat, solprt, statpr, vneed,
+!el 4 vsave, x0prt
+!
+! *** iv subscript values ***
+!
+!/6
+! data algsav/51/, covprt/14/, covreq/15/, dtype/16/, hc/71/,
+! 1 ierr/75/, inith/25/, inits/25/, ipivot/76/, ivneed/3/,
+! 2 lastiv/44/, lastv/45/, lmat/42/, mxfcal/17/, mxiter/18/,
+! 3 nfcov/52/, ngcov/53/, nvdflt/50/, outlev/19/, parprt/20/,
+! 4 parsav/49/, perm/58/, prunit/21/, qrtyp/80/, rdreq/57/,
+! 5 rmat/78/, solprt/22/, statpr/23/, vneed/4/, vsave/60/,
+! 6 x0prt/24/
+!/7
+ integer,parameter :: algsav=51, covprt=14, covreq=15, dtype=16, hc=71,&
+ ierr=75, inith=25, inits=25, ipivot=76, ivneed=3,&
+ lastiv=44, lastv=45, lmat=42, mxfcal=17, mxiter=18,&
+ nfcov=52, ngcov=53, nvdflt=50, outlev=19, parprt=20,&
+ parsav=49, perm=58, prunit=21, qrtyp=80, rdreq=57,&
+ rmat=78, solprt=22, statpr=23, vneed=4, vsave=60,&
+ x0prt=24
+!/
+ data miniv(1)/80/, miniv(2)/59/, minv(1)/98/, minv(2)/71/
+!el local variables
+ integer :: mv
+!
+!------------------------------- body --------------------------------
+!
+ if (alg .lt. 1 .or. alg .gt. 2) go to 40
+ miv = miniv(alg)
+ if (liv .lt. miv) go to 20
+ mv = minv(alg)
+ if (lv .lt. mv) go to 30
+ call vdflt(alg, lv, v)
+ iv(1) = 12
+ iv(algsav) = alg
+ iv(ivneed) = 0
+ iv(lastiv) = miv
+ iv(lastv) = mv
+ iv(lmat) = mv + 1
+ iv(mxfcal) = 200
+ iv(mxiter) = 150
+ iv(outlev) = 1
+ iv(parprt) = 1
+ iv(perm) = miv + 1
+ iv(prunit) = imdcon(1)
+ iv(solprt) = 1
+ iv(statpr) = 1
+ iv(vneed) = 0
+ iv(x0prt) = 1
+!
+ if (alg .ge. 2) go to 10
+!
+! *** regression values
+!
+ iv(covprt) = 3
+ iv(covreq) = 1
+ iv(dtype) = 1
+ iv(hc) = 0
+ iv(ierr) = 0
+ iv(inits) = 0
+ iv(ipivot) = 0
+ iv(nvdflt) = 32
+ iv(parsav) = 67
+ iv(qrtyp) = 1
+ iv(rdreq) = 3
+ iv(rmat) = 0
+ iv(vsave) = 58
+ go to 999
+!
+! *** general optimization values
+!
+ 10 iv(dtype) = 0
+ iv(inith) = 1
+ iv(nfcov) = 0
+ iv(ngcov) = 0
+ iv(nvdflt) = 25
+ iv(parsav) = 47
+ go to 999
+!
+ 20 iv(1) = 15
+ go to 999
+!
+ 30 iv(1) = 16
+ go to 999
+!
+ 40 iv(1) = 67
+!
+ 999 return
+! *** last card of deflt follows ***
+ end subroutine deflt
+!-----------------------------------------------------------------------------
+ real(kind=8) function dotprd(p,x,y)
+!
+! *** return the inner product of the p-vectors x and y. ***
+!
+ integer :: p
+ real(kind=8) :: x(p), y(p)
+!
+ integer :: i
+!el real(kind=8) :: one, zero
+ real(kind=8) :: sqteta, t
+!/+
+!el real(kind=8) :: dmax1, dabs
+!/
+!el external rmdcon
+!el real(kind=8) :: rmdcon
+!
+! *** rmdcon(2) returns a machine-dependent constant, sqteta, which
+! *** is slightly larger than the smallest positive number that
+! *** can be squared without underflowing.
+!
+!/6
+! data one/1.d+0/, sqteta/0.d+0/, zero/0.d+0/
+!/7
+ real(kind=8),parameter :: one=1.d+0, zero=0.d+0
+ data sqteta/0.d+0/
+!/
+!
+ dotprd = zero
+ if (p .le. 0) go to 999
+!rc if (sqteta .eq. zero) sqteta = rmdcon(2)
+ do 20 i = 1, p
+!rc t = dmax1(dabs(x(i)), dabs(y(i)))
+!rc if (t .gt. one) go to 10
+!rc if (t .lt. sqteta) go to 20
+!rc t = (x(i)/sqteta)*y(i)
+!rc if (dabs(t) .lt. sqteta) go to 20
+ 10 dotprd = dotprd + x(i)*y(i)
+ 20 continue
+!
+ 999 return
+! *** last card of dotprd follows ***
+ end function dotprd
+!-----------------------------------------------------------------------------
+ subroutine itsum(d, g, iv, liv, lv, p, v, x)
+!
+! *** print iteration summary for ***sol (version 2.3) ***
+!
+! *** parameter declarations ***
+!
+ integer :: liv, lv, p
+ integer :: iv(liv)
+ real(kind=8) :: d(p), g(p), v(lv), x(p)
+!
+!+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+!
+! *** local variables ***
+!
+ integer :: alg, i, iv1, m, nf, ng, ol, pu
+!/6
+! real model1(6), model2(6)
+!/7
+ character(len=4) :: model1(6), model2(6)
+!/
+ real(kind=8) :: nreldf, oldf, preldf, reldf !el, zero
+!
+! *** intrinsic functions ***
+!/+
+!el integer :: iabs
+!el real(kind=8) :: dabs, dmax1
+!/
+! *** no external functions or subroutines ***
+!
+! *** subscripts for iv and v ***
+!
+!el integer algsav, dstnrm, f, fdif, f0, needhd, nfcall, nfcov, ngcov,
+!el 1 ngcall, niter, nreduc, outlev, preduc, prntit, prunit,
+!el 2 reldx, solprt, statpr, stppar, sused, x0prt
+!
+! *** iv subscript values ***
+!
+!/6
+! data algsav/51/, needhd/36/, nfcall/6/, nfcov/52/, ngcall/30/,
+! 1 ngcov/53/, niter/31/, outlev/19/, prntit/39/, prunit/21/,
+! 2 solprt/22/, statpr/23/, sused/64/, x0prt/24/
+!/7
+ integer,parameter :: algsav=51, needhd=36, nfcall=6, nfcov=52, ngcall=30,&
+ ngcov=53, niter=31, outlev=19, prntit=39, prunit=21,&
+ solprt=22, statpr=23, sused=64, x0prt=24
+!/
+!
+! *** v subscript values ***
+!
+!/6
+! data dstnrm/2/, f/10/, f0/13/, fdif/11/, nreduc/6/, preduc/7/,
+! 1 reldx/17/, stppar/5/
+!/7
+ integer,parameter :: dstnrm=2, f=10, f0=13, fdif=11, nreduc=6, preduc=7,&
+ reldx=17, stppar=5
+!/
+!
+!/6
+! data zero/0.d+0/
+!/7
+ real(kind=8),parameter :: zero=0.d+0
+!/
+!/6
+! data model1(1)/4h /, model1(2)/4h /, model1(3)/4h /,
+! 1 model1(4)/4h /, model1(5)/4h g /, model1(6)/4h s /,
+! 2 model2(1)/4h g /, model2(2)/4h s /, model2(3)/4hg-s /,
+! 3 model2(4)/4hs-g /, model2(5)/4h-s-g/, model2(6)/4h-g-s/
+!/7
+ data model1/' ',' ',' ',' ',' g ',' s '/,&
+ model2/' g ',' s ','g-s ','s-g ','-s-g','-g-s'/
+!/
+!
+!------------------------------- body --------------------------------
+!
+ pu = iv(prunit)
+ if (pu .eq. 0) go to 999
+ iv1 = iv(1)
+ if (iv1 .gt. 62) iv1 = iv1 - 51
+ ol = iv(outlev)
+ alg = iv(algsav)
+ if (iv1 .lt. 2 .or. iv1 .gt. 15) go to 370
+ if (iv1 .ge. 12) go to 120
+ if (iv1 .eq. 2 .and. iv(niter) .eq. 0) go to 390
+ if (ol .eq. 0) go to 120
+ if (iv1 .ge. 10 .and. iv(prntit) .eq. 0) go to 120
+ if (iv1 .gt. 2) go to 10
+ iv(prntit) = iv(prntit) + 1
+ if (iv(prntit) .lt. iabs(ol)) go to 999
+ 10 nf = iv(nfcall) - iabs(iv(nfcov))
+ iv(prntit) = 0
+ reldf = zero
+ preldf = zero
+ oldf = dmax1(dabs(v(f0)), dabs(v(f)))
+ if (oldf .le. zero) go to 20
+ reldf = v(fdif) / oldf
+ preldf = v(preduc) / oldf
+ 20 if (ol .gt. 0) go to 60
+!
+! *** print short summary line ***
+!
+ if (iv(needhd) .eq. 1 .and. alg .eq. 1) write(pu,30)
+ 30 format(/10h it nf,6x,1hf,7x,5hreldf,3x,6hpreldf,3x,5hreldx,&
+ 2x,13hmodel stppar)
+ if (iv(needhd) .eq. 1 .and. alg .eq. 2) write(pu,40)
+ 40 format(/11h it nf,7x,1hf,8x,5hreldf,4x,6hpreldf,4x,5hreldx,&
+ 3x,6hstppar)
+ iv(needhd) = 0
+ if (alg .eq. 2) go to 50
+ m = iv(sused)
+ write(pu,100) iv(niter), nf, v(f), reldf, preldf, v(reldx),&
+ model1(m), model2(m), v(stppar)
+ go to 120
+!
+ 50 write(pu,110) iv(niter), nf, v(f), reldf, preldf, v(reldx),&
+ v(stppar)
+ go to 120
+!
+! *** print long summary line ***
+!
+ 60 if (iv(needhd) .eq. 1 .and. alg .eq. 1) write(pu,70)
+ 70 format(/11h it nf,6x,1hf,7x,5hreldf,3x,6hpreldf,3x,5hreldx,&
+ 2x,13hmodel stppar,2x,6hd*step,2x,7hnpreldf)
+ if (iv(needhd) .eq. 1 .and. alg .eq. 2) write(pu,80)
+ 80 format(/11h it nf,7x,1hf,8x,5hreldf,4x,6hpreldf,4x,5hreldx,&
+ 3x,6hstppar,3x,6hd*step,3x,7hnpreldf)
+ iv(needhd) = 0
+ nreldf = zero
+ if (oldf .gt. zero) nreldf = v(nreduc) / oldf
+ if (alg .eq. 2) go to 90
+ m = iv(sused)
+ write(pu,100) iv(niter), nf, v(f), reldf, preldf, v(reldx),&
+ model1(m), model2(m), v(stppar), v(dstnrm), nreldf
+ go to 120
+!
+ 90 write(pu,110) iv(niter), nf, v(f), reldf, preldf,&
+ v(reldx), v(stppar), v(dstnrm), nreldf
+ 100 format(i6,i5,d10.3,2d9.2,d8.1,a3,a4,2d8.1,d9.2)
+ 110 format(i6,i5,d11.3,2d10.2,3d9.1,d10.2)
+!
+ 120 if (iv(statpr) .lt. 0) go to 430
+ go to (999, 999, 130, 150, 170, 190, 210, 230, 250, 270, 290, 310,&
+ 330, 350, 520), iv1
+!
+ 130 write(pu,140)
+ 140 format(/26h ***** x-convergence *****)
+ go to 430
+!
+ 150 write(pu,160)
+ 160 format(/42h ***** relative function convergence *****)
+ go to 430
+!
+ 170 write(pu,180)
+ 180 format(/49h ***** x- and relative function convergence *****)
+ go to 430
+!
+ 190 write(pu,200)
+ 200 format(/42h ***** absolute function convergence *****)
+ go to 430
+!
+ 210 write(pu,220)
+ 220 format(/33h ***** singular convergence *****)
+ go to 430
+!
+ 230 write(pu,240)
+ 240 format(/30h ***** false convergence *****)
+ go to 430
+!
+ 250 write(pu,260)
+ 260 format(/38h ***** function evaluation limit *****)
+ go to 430
+!
+ 270 write(pu,280)
+ 280 format(/28h ***** iteration limit *****)
+ go to 430
+!
+ 290 write(pu,300)
+ 300 format(/18h ***** stopx *****)
+ go to 430
+!
+ 310 write(pu,320)
+ 320 format(/44h ***** initial f(x) cannot be computed *****)
+!
+ go to 390
+!
+ 330 write(pu,340)
+ 340 format(/37h ***** bad parameters to assess *****)
+ go to 999
+!
+ 350 write(pu,360)
+ 360 format(/43h ***** gradient could not be computed *****)
+ if (iv(niter) .gt. 0) go to 480
+ go to 390
+!
+ 370 write(pu,380) iv(1)
+ 380 format(/14h ***** iv(1) =,i5,6h *****)
+ go to 999
+!
+! *** initial call on itsum ***
+!
+ 390 if (iv(x0prt) .ne. 0) write(pu,400) (i, x(i), d(i), i = 1, p)
+ 400 format(/23h i initial x(i),8x,4hd(i)//(1x,i5,d17.6,d14.3))
+! *** the following are to avoid undefined variables when the
+! *** function evaluation limit is 1...
+ v(dstnrm) = zero
+ v(fdif) = zero
+ v(nreduc) = zero
+ v(preduc) = zero
+ v(reldx) = zero
+ if (iv1 .ge. 12) go to 999
+ iv(needhd) = 0
+ iv(prntit) = 0
+ if (ol .eq. 0) go to 999
+ if (ol .lt. 0 .and. alg .eq. 1) write(pu,30)
+ if (ol .lt. 0 .and. alg .eq. 2) write(pu,40)
+ if (ol .gt. 0 .and. alg .eq. 1) write(pu,70)
+ if (ol .gt. 0 .and. alg .eq. 2) write(pu,80)
+ if (alg .eq. 1) write(pu,410) v(f)
+ if (alg .eq. 2) write(pu,420) v(f)
+ 410 format(/11h 0 1,d10.3)
+!365 format(/11h 0 1,e11.3)
+ 420 format(/11h 0 1,d11.3)
+ go to 999
+!
+! *** print various information requested on solution ***
+!
+ 430 iv(needhd) = 1
+ if (iv(statpr) .eq. 0) go to 480
+ oldf = dmax1(dabs(v(f0)), dabs(v(f)))
+ preldf = zero
+ nreldf = zero
+ if (oldf .le. zero) go to 440
+ preldf = v(preduc) / oldf
+ nreldf = v(nreduc) / oldf
+ 440 nf = iv(nfcall) - iv(nfcov)
+ ng = iv(ngcall) - iv(ngcov)
+ write(pu,450) v(f), v(reldx), nf, ng, preldf, nreldf
+ 450 format(/9h function,d17.6,8h reldx,d17.3/12h func. evals,&
+ i8,9x,11hgrad. evals,i8/7h preldf,d16.3,6x,7hnpreldf,d15.3)
+!
+ if (iv(nfcov) .gt. 0) write(pu,460) iv(nfcov)
+ 460 format(/1x,i4,50h extra func. evals for covariance and diagnostics.)
+ if (iv(ngcov) .gt. 0) write(pu,470) iv(ngcov)
+ 470 format(1x,i4,50h extra grad. evals for covariance and diagnostics.)
+!
+ 480 if (iv(solprt) .eq. 0) go to 999
+ iv(needhd) = 1
+ write(pu,490)
+ 490 format(/22h i final x(i),8x,4hd(i),10x,4hg(i)/)
+ do 500 i = 1, p
+ write(pu,510) i, x(i), d(i), g(i)
+ 500 continue
+ 510 format(1x,i5,d16.6,2d14.3)
+ go to 999
+!
+ 520 write(pu,530)
+ 530 format(/24h inconsistent dimensions)
+ 999 return
+! *** last card of itsum follows ***
+ end subroutine itsum
+!-----------------------------------------------------------------------------
+ subroutine litvmu(n, x, l, y)
+!
+! *** solve (l**t)*x = y, where l is an n x n lower triangular
+! *** matrix stored compactly by rows. x and y may occupy the same
+! *** storage. ***
+!
+ integer :: n
+!al real(kind=8) :: x(n), l(1), y(n)
+ real(kind=8) :: x(n), l(n*(n+1)/2), y(n)
+ integer :: i, ii, ij, im1, i0, j, np1
+ real(kind=8) :: xi !el, zero
+!/6
+! data zero/0.d+0/
+!/7
+ real(kind=8),parameter :: zero=0.d+0
+!/
+!
+ do 10 i = 1, n
+ 10 x(i) = y(i)
+ np1 = n + 1
+ i0 = n*(n+1)/2
+ do 30 ii = 1, n
+ i = np1 - ii
+ xi = x(i)/l(i0)
+ x(i) = xi
+ if (i .le. 1) go to 999
+ i0 = i0 - i
+ if (xi .eq. zero) go to 30
+ im1 = i - 1
+ do 20 j = 1, im1
+ ij = i0 + j
+ x(j) = x(j) - xi*l(ij)
+ 20 continue
+ 30 continue
+ 999 return
+! *** last card of litvmu follows ***
+ end subroutine litvmu
+!-----------------------------------------------------------------------------
+ subroutine livmul(n, x, l, y)
+!
+! *** solve l*x = y, where l is an n x n lower triangular
+! *** matrix stored compactly by rows. x and y may occupy the same
+! *** storage. ***
+!
+ integer :: n
+!al real(kind=8) :: x(n), l(1), y(n)
+ real(kind=8) :: x(n), l(n*(n+1)/2), y(n)
+!el external dotprd
+!el real(kind=8) :: dotprd
+ integer :: i, j, k
+ real(kind=8) :: t !el, zero
+!/6
+! data zero/0.d+0/
+!/7
+ real(kind=8),parameter :: zero=0.d+0
+!/
+!
+ do 10 k = 1, n
+ if (y(k) .ne. zero) go to 20
+ x(k) = zero
+ 10 continue
+ go to 999
+ 20 j = k*(k+1)/2
+ x(k) = y(k) / l(j)
+ if (k .ge. n) go to 999
+ k = k + 1
+ do 30 i = k, n
+ t = dotprd(i-1, l(j+1), x)
+ j = j + i
+ x(i) = (y(i) - t)/l(j)
+ 30 continue
+ 999 return
+! *** last card of livmul follows ***
+ end subroutine livmul
+!-----------------------------------------------------------------------------
+ subroutine parck(alg, d, iv, liv, lv, n, v)
+!
+! *** check ***sol (version 2.3) parameters, print changed values ***
+!
+! *** alg = 1 for regression, alg = 2 for general unconstrained opt.
+!
+ integer :: alg, liv, lv, n
+ integer :: iv(liv)
+ real(kind=8) :: d(n), v(lv)
+!
+!el external rmdcon, vcopy, vdflt
+!el real(kind=8) :: rmdcon
+! rmdcon -- returns machine-dependent constants.
+! vcopy -- copies one vector to another.
+! vdflt -- supplies default parameter values to v alone.
+!/+
+!el integer :: max0
+!/
+!
+! *** local variables ***
+!
+ integer :: i, ii, iv1, j, k, l, m, miv1, miv2, ndfalt, parsv1, pu
+ integer :: ijmp, jlim(2), miniv(2), ndflt(2)
+!/6
+! integer varnm(2), sh(2)
+! real cngd(3), dflt(3), vn(2,34), which(3)
+!/7
+ character(len=1) :: varnm(2), sh(2)
+ character(len=4) :: cngd(3), dflt(3), vn(2,34), which(3)
+!/
+ real(kind=8) :: big, machep, tiny, vk, vm(34), vx(34), zero
+!
+! *** iv and v subscripts ***
+!
+!el integer algsav, dinit, dtype, dtype0, epslon, inits, ivneed,
+!el 1 lastiv, lastv, lmat, nextiv, nextv, nvdflt, oldn,
+!el 2 parprt, parsav, perm, prunit, vneed
+!
+!
+!/6
+! data algsav/51/, dinit/38/, dtype/16/, dtype0/54/, epslon/19/,
+! 1 inits/25/, ivneed/3/, lastiv/44/, lastv/45/, lmat/42/,
+! 2 nextiv/46/, nextv/47/, nvdflt/50/, oldn/38/, parprt/20/,
+! 3 parsav/49/, perm/58/, prunit/21/, vneed/4/
+!/7
+ integer,parameter :: algsav=51, dinit=38, dtype=16, dtype0=54, epslon=19,&
+ inits=25, ivneed=3, lastiv=44, lastv=45, lmat=42,&
+ nextiv=46, nextv=47, nvdflt=50, oldn=38, parprt=20,&
+ parsav=49, perm=58, prunit=21, vneed=4
+ save big, machep, tiny
+!/
+!
+ data big/0.d+0/, machep/-1.d+0/, tiny/1.d+0/, zero/0.d+0/
+!/6
+! data vn(1,1),vn(2,1)/4hepsl,4hon../
+! data vn(1,2),vn(2,2)/4hphmn,4hfc../
+! data vn(1,3),vn(2,3)/4hphmx,4hfc../
+! data vn(1,4),vn(2,4)/4hdecf,4hac../
+! data vn(1,5),vn(2,5)/4hincf,4hac../
+! data vn(1,6),vn(2,6)/4hrdfc,4hmn../
+! data vn(1,7),vn(2,7)/4hrdfc,4hmx../
+! data vn(1,8),vn(2,8)/4htune,4hr1../
+! data vn(1,9),vn(2,9)/4htune,4hr2../
+! data vn(1,10),vn(2,10)/4htune,4hr3../
+! data vn(1,11),vn(2,11)/4htune,4hr4../
+! data vn(1,12),vn(2,12)/4htune,4hr5../
+! data vn(1,13),vn(2,13)/4hafct,4hol../
+! data vn(1,14),vn(2,14)/4hrfct,4hol../
+! data vn(1,15),vn(2,15)/4hxcto,4hl.../
+! data vn(1,16),vn(2,16)/4hxfto,4hl.../
+! data vn(1,17),vn(2,17)/4hlmax,4h0.../
+! data vn(1,18),vn(2,18)/4hlmax,4hs.../
+! data vn(1,19),vn(2,19)/4hscto,4hl.../
+! data vn(1,20),vn(2,20)/4hdini,4ht.../
+! data vn(1,21),vn(2,21)/4hdtin,4hit../
+! data vn(1,22),vn(2,22)/4hd0in,4hit../
+! data vn(1,23),vn(2,23)/4hdfac,4h..../
+! data vn(1,24),vn(2,24)/4hdltf,4hdc../
+! data vn(1,25),vn(2,25)/4hdltf,4hdj../
+! data vn(1,26),vn(2,26)/4hdelt,4ha0../
+! data vn(1,27),vn(2,27)/4hfuzz,4h..../
+! data vn(1,28),vn(2,28)/4hrlim,4hit../
+! data vn(1,29),vn(2,29)/4hcosm,4hin../
+! data vn(1,30),vn(2,30)/4hhube,4hrc../
+! data vn(1,31),vn(2,31)/4hrspt,4hol../
+! data vn(1,32),vn(2,32)/4hsigm,4hin../
+! data vn(1,33),vn(2,33)/4heta0,4h..../
+! data vn(1,34),vn(2,34)/4hbias,4h..../
+!/7
+ data vn(1,1),vn(2,1)/'epsl','on..'/
+ data vn(1,2),vn(2,2)/'phmn','fc..'/
+ data vn(1,3),vn(2,3)/'phmx','fc..'/
+ data vn(1,4),vn(2,4)/'decf','ac..'/
+ data vn(1,5),vn(2,5)/'incf','ac..'/
+ data vn(1,6),vn(2,6)/'rdfc','mn..'/
+ data vn(1,7),vn(2,7)/'rdfc','mx..'/
+ data vn(1,8),vn(2,8)/'tune','r1..'/
+ data vn(1,9),vn(2,9)/'tune','r2..'/
+ data vn(1,10),vn(2,10)/'tune','r3..'/
+ data vn(1,11),vn(2,11)/'tune','r4..'/
+ data vn(1,12),vn(2,12)/'tune','r5..'/
+ data vn(1,13),vn(2,13)/'afct','ol..'/
+ data vn(1,14),vn(2,14)/'rfct','ol..'/
+ data vn(1,15),vn(2,15)/'xcto','l...'/
+ data vn(1,16),vn(2,16)/'xfto','l...'/
+ data vn(1,17),vn(2,17)/'lmax','0...'/
+ data vn(1,18),vn(2,18)/'lmax','s...'/
+ data vn(1,19),vn(2,19)/'scto','l...'/
+ data vn(1,20),vn(2,20)/'dini','t...'/
+ data vn(1,21),vn(2,21)/'dtin','it..'/
+ data vn(1,22),vn(2,22)/'d0in','it..'/
+ data vn(1,23),vn(2,23)/'dfac','....'/
+ data vn(1,24),vn(2,24)/'dltf','dc..'/
+ data vn(1,25),vn(2,25)/'dltf','dj..'/
+ data vn(1,26),vn(2,26)/'delt','a0..'/
+ data vn(1,27),vn(2,27)/'fuzz','....'/
+ data vn(1,28),vn(2,28)/'rlim','it..'/
+ data vn(1,29),vn(2,29)/'cosm','in..'/
+ data vn(1,30),vn(2,30)/'hube','rc..'/
+ data vn(1,31),vn(2,31)/'rspt','ol..'/
+ data vn(1,32),vn(2,32)/'sigm','in..'/
+ data vn(1,33),vn(2,33)/'eta0','....'/
+ data vn(1,34),vn(2,34)/'bias','....'/
+!/
+!
+ data vm(1)/1.0d-3/, vm(2)/-0.99d+0/, vm(3)/1.0d-3/, vm(4)/1.0d-2/,&
+ vm(5)/1.2d+0/, vm(6)/1.d-2/, vm(7)/1.2d+0/, vm(8)/0.d+0/,&
+ vm(9)/0.d+0/, vm(10)/1.d-3/, vm(11)/-1.d+0/, vm(13)/0.d+0/,&
+ vm(15)/0.d+0/, vm(16)/0.d+0/, vm(19)/0.d+0/, vm(20)/-10.d+0/,&
+ vm(21)/0.d+0/, vm(22)/0.d+0/, vm(23)/0.d+0/, vm(27)/1.01d+0/,&
+ vm(28)/1.d+10/, vm(30)/0.d+0/, vm(31)/0.d+0/, vm(32)/0.d+0/,&
+ vm(34)/0.d+0/
+ data vx(1)/0.9d+0/, vx(2)/-1.d-3/, vx(3)/1.d+1/, vx(4)/0.8d+0/,&
+ vx(5)/1.d+2/, vx(6)/0.8d+0/, vx(7)/1.d+2/, vx(8)/0.5d+0/,&
+ vx(9)/0.5d+0/, vx(10)/1.d+0/, vx(11)/1.d+0/, vx(14)/0.1d+0/,&
+ vx(15)/1.d+0/, vx(16)/1.d+0/, vx(19)/1.d+0/, vx(23)/1.d+0/,&
+ vx(24)/1.d+0/, vx(25)/1.d+0/, vx(26)/1.d+0/, vx(27)/1.d+10/,&
+ vx(29)/1.d+0/, vx(31)/1.d+0/, vx(32)/1.d+0/, vx(33)/1.d+0/,&
+ vx(34)/1.d+0/
+!
+!/6
+! data varnm(1)/1hp/, varnm(2)/1hn/, sh(1)/1hs/, sh(2)/1hh/
+! data cngd(1),cngd(2),cngd(3)/4h---c,4hhang,4hed v/,
+! 1 dflt(1),dflt(2),dflt(3)/4hnond,4hefau,4hlt v/
+!/7
+ data varnm(1)/'p'/, varnm(2)/'n'/, sh(1)/'s'/, sh(2)/'h'/
+ data cngd(1),cngd(2),cngd(3)/'---c','hang','ed v'/,&
+ dflt(1),dflt(2),dflt(3)/'nond','efau','lt v'/
+!/
+ data ijmp/33/, jlim(1)/0/, jlim(2)/24/, ndflt(1)/32/, ndflt(2)/25/
+ data miniv(1)/80/, miniv(2)/59/
+!
+!............................... body ................................
+!
+ pu = 0
+ if (prunit .le. liv) pu = iv(prunit)
+ if (alg .lt. 1 .or. alg .gt. 2) go to 340
+ if (iv(1) .eq. 0) call deflt(alg, iv, liv, lv, v)
+ iv1 = iv(1)
+ if (iv1 .ne. 13 .and. iv1 .ne. 12) go to 10
+ miv1 = miniv(alg)
+ if (perm .le. liv) miv1 = max0(miv1, iv(perm) - 1)
+ if (ivneed .le. liv) miv2 = miv1 + max0(iv(ivneed), 0)
+ if (lastiv .le. liv) iv(lastiv) = miv2
+ if (liv .lt. miv1) go to 300
+ iv(ivneed) = 0
+ iv(lastv) = max0(iv(vneed), 0) + iv(lmat) - 1
+ iv(vneed) = 0
+ if (liv .lt. miv2) go to 300
+ if (lv .lt. iv(lastv)) go to 320
+ 10 if (alg .eq. iv(algsav)) go to 30
+ if (pu .ne. 0) write(pu,20) alg, iv(algsav)
+ 20 format(/39h the first parameter to deflt should be,i3,&
+ 12h rather than,i3)
+ iv(1) = 82
+ go to 999
+ 30 if (iv1 .lt. 12 .or. iv1 .gt. 14) go to 60
+ if (n .ge. 1) go to 50
+ iv(1) = 81
+ if (pu .eq. 0) go to 999
+ write(pu,40) varnm(alg), n
+ 40 format(/8h /// bad,a1,2h =,i5)
+ go to 999
+ 50 if (iv1 .ne. 14) iv(nextiv) = iv(perm)
+ if (iv1 .ne. 14) iv(nextv) = iv(lmat)
+ if (iv1 .eq. 13) go to 999
+ k = iv(parsav) - epslon
+ call vdflt(alg, lv-k, v(k+1))
+ iv(dtype0) = 2 - alg
+ iv(oldn) = n
+ which(1) = dflt(1)
+ which(2) = dflt(2)
+ which(3) = dflt(3)
+ go to 110
+ 60 if (n .eq. iv(oldn)) go to 80
+ iv(1) = 17
+ if (pu .eq. 0) go to 999
+ write(pu,70) varnm(alg), iv(oldn), n
+ 70 format(/5h /// ,1a1,14h changed from ,i5,4h to ,i5)
+ go to 999
+!
+ 80 if (iv1 .le. 11 .and. iv1 .ge. 1) go to 100
+ iv(1) = 80
+ if (pu .ne. 0) write(pu,90) iv1
+ 90 format(/13h /// iv(1) =,i5,28h should be between 0 and 14.)
+ go to 999
+!
+ 100 which(1) = cngd(1)
+ which(2) = cngd(2)
+ which(3) = cngd(3)
+!
+ 110 if (iv1 .eq. 14) iv1 = 12
+ if (big .gt. tiny) go to 120
+ tiny = rmdcon(1)
+ machep = rmdcon(3)
+ big = rmdcon(6)
+ vm(12) = machep
+ vx(12) = big
+ vx(13) = big
+ vm(14) = machep
+ vm(17) = tiny
+ vx(17) = big
+ vm(18) = tiny
+ vx(18) = big
+ vx(20) = big
+ vx(21) = big
+ vx(22) = big
+ vm(24) = machep
+ vm(25) = machep
+ vm(26) = machep
+ vx(28) = rmdcon(5)
+ vm(29) = machep
+ vx(30) = big
+ vm(33) = machep
+ 120 m = 0
+ i = 1
+ j = jlim(alg)
+ k = epslon
+ ndfalt = ndflt(alg)
+ do 150 l = 1, ndfalt
+ vk = v(k)
+ if (vk .ge. vm(i) .and. vk .le. vx(i)) go to 140
+ m = k
+ if (pu .ne. 0) write(pu,130) vn(1,i), vn(2,i), k, vk,&
+ vm(i), vx(i)
+ 130 format(/6h /// ,2a4,5h.. v(,i2,3h) =,d11.3,7h should,&
+ 11h be between,d11.3,4h and,d11.3)
+ 140 k = k + 1
+ i = i + 1
+ if (i .eq. j) i = ijmp
+ 150 continue
+!
+ if (iv(nvdflt) .eq. ndfalt) go to 170
+ iv(1) = 51
+ if (pu .eq. 0) go to 999
+ write(pu,160) iv(nvdflt), ndfalt
+ 160 format(/13h iv(nvdflt) =,i5,13h rather than ,i5)
+ go to 999
+ 170 if ((iv(dtype) .gt. 0 .or. v(dinit) .gt. zero) .and. iv1 .eq. 12) &
+ go to 200
+ do 190 i = 1, n
+ if (d(i) .gt. zero) go to 190
+ m = 18
+ if (pu .ne. 0) write(pu,180) i, d(i)
+ 180 format(/8h /// d(,i3,3h) =,d11.3,19h should be positive)
+ 190 continue
+ 200 if (m .eq. 0) go to 210
+ iv(1) = m
+ go to 999
+!
+ 210 if (pu .eq. 0 .or. iv(parprt) .eq. 0) go to 999
+ if (iv1 .ne. 12 .or. iv(inits) .eq. alg-1) go to 230
+ m = 1
+ write(pu,220) sh(alg), iv(inits)
+ 220 format(/22h nondefault values..../5h init,a1,14h..... iv(25) =,&
+ i3)
+ 230 if (iv(dtype) .eq. iv(dtype0)) go to 250
+ if (m .eq. 0) write(pu,260) which
+ m = 1
+ write(pu,240) iv(dtype)
+ 240 format(20h dtype..... iv(16) =,i3)
+ 250 i = 1
+ j = jlim(alg)
+ k = epslon
+ l = iv(parsav)
+ ndfalt = ndflt(alg)
+ do 290 ii = 1, ndfalt
+ if (v(k) .eq. v(l)) go to 280
+ if (m .eq. 0) write(pu,260) which
+ 260 format(/1h ,3a4,9halues..../)
+ m = 1
+ write(pu,270) vn(1,i), vn(2,i), k, v(k)
+ 270 format(1x,2a4,5h.. v(,i2,3h) =,d15.7)
+ 280 k = k + 1
+ l = l + 1
+ i = i + 1
+ if (i .eq. j) i = ijmp
+ 290 continue
+!
+ iv(dtype0) = iv(dtype)
+ parsv1 = iv(parsav)
+ call vcopy(iv(nvdflt), v(parsv1), v(epslon))
+ go to 999
+!
+ 300 iv(1) = 15
+ if (pu .eq. 0) go to 999
+ write(pu,310) liv, miv2
+ 310 format(/10h /// liv =,i5,17h must be at least,i5)
+ if (liv .lt. miv1) go to 999
+ if (lv .lt. iv(lastv)) go to 320
+ go to 999
+!
+ 320 iv(1) = 16
+ if (pu .eq. 0) go to 999
+ write(pu,330) lv, iv(lastv)
+ 330 format(/9h /// lv =,i5,17h must be at least,i5)
+ go to 999
+!
+ 340 iv(1) = 67
+ if (pu .eq. 0) go to 999
+ write(pu,350) alg
+ 350 format(/10h /// alg =,i5,15h must be 1 or 2)
+!
+ 999 return
+! *** last card of parck follows ***
+ end subroutine parck
+!-----------------------------------------------------------------------------
+ real(kind=8) function reldst(p, d, x, x0)
+!
+! *** compute and return relative difference between x and x0 ***
+! *** nl2sol version 2.2 ***
+!
+ integer :: p
+ real(kind=8) :: d(p), x(p), x0(p)
+!/+
+!el real(kind=8) :: dabs
+!/
+ integer :: i
+ real(kind=8) :: emax, t, xmax !el, zero
+!/6
+! data zero/0.d+0/
+!/7
+ real(kind=8),parameter :: zero=0.d+0
+!/
+!
+ emax = zero
+ xmax = zero
+ do 10 i = 1, p
+ t = dabs(d(i) * (x(i) - x0(i)))
+ if (emax .lt. t) emax = t
+ t = d(i) * (dabs(x(i)) + dabs(x0(i)))
+ if (xmax .lt. t) xmax = t
+ 10 continue
+ reldst = zero
+ if (xmax .gt. zero) reldst = emax / xmax
+ 999 return
+! *** last card of reldst follows ***
+ end function reldst
+!-----------------------------------------------------------------------------
+ subroutine vaxpy(p, w, a, x, y)
+!
+! *** set w = a*x + y -- w, x, y = p-vectors, a = scalar ***
+!
+ integer :: p
+ real(kind=8) :: a, w(p), x(p), y(p)
+!
+ integer :: i
+!
+ do 10 i = 1, p
+ 10 w(i) = a*x(i) + y(i)
+ return
+ end subroutine vaxpy
+!-----------------------------------------------------------------------------
+ subroutine vcopy(p, y, x)
+!
+! *** set y = x, where x and y are p-vectors ***
+!
+ integer :: p
+ real(kind=8) :: x(p), y(p)
+!
+ integer :: i
+!
+ do 10 i = 1, p
+ 10 y(i) = x(i)
+ return
+ end subroutine vcopy
+!-----------------------------------------------------------------------------
+ subroutine vdflt(alg, lv, v)
+!
+! *** supply ***sol (version 2.3) default values to v ***
+!
+! *** alg = 1 means regression constants.
+! *** alg = 2 means general unconstrained optimization constants.
+!
+ integer :: alg, l,lv
+ real(kind=8) :: v(lv)
+!/+
+!el real(kind=8) :: dmax1
+!/
+!el external rmdcon
+!el real(kind=8) :: rmdcon
+! rmdcon... returns machine-dependent constants
+!
+ real(kind=8) :: machep, mepcrt, sqteps !el one, three
+!
+! *** subscripts for v ***
+!
+!el integer afctol, bias, cosmin, decfac, delta0, dfac, dinit, dltfdc,
+!el 1 dltfdj, dtinit, d0init, epslon, eta0, fuzz, huberc,
+!el 2 incfac, lmax0, lmaxs, phmnfc, phmxfc, rdfcmn, rdfcmx,
+!el 3 rfctol, rlimit, rsptol, sctol, sigmin, tuner1, tuner2,
+!el 4 tuner3, tuner4, tuner5, xctol, xftol
+!
+!/6
+! data one/1.d+0/, three/3.d+0/
+!/7
+ real(kind=8),parameter :: one=1.d+0, three=3.d+0
+!/
+!
+! *** v subscript values ***
+!
+!/6
+! data afctol/31/, bias/43/, cosmin/47/, decfac/22/, delta0/44/,
+! 1 dfac/41/, dinit/38/, dltfdc/42/, dltfdj/43/, dtinit/39/,
+! 2 d0init/40/, epslon/19/, eta0/42/, fuzz/45/, huberc/48/,
+! 3 incfac/23/, lmax0/35/, lmaxs/36/, phmnfc/20/, phmxfc/21/,
+! 4 rdfcmn/24/, rdfcmx/25/, rfctol/32/, rlimit/46/, rsptol/49/,
+! 5 sctol/37/, sigmin/50/, tuner1/26/, tuner2/27/, tuner3/28/,
+! 6 tuner4/29/, tuner5/30/, xctol/33/, xftol/34/
+!/7
+ integer,parameter :: afctol=31, bias=43, cosmin=47, decfac=22, delta0=44,&
+ dfac=41, dinit=38, dltfdc=42, dltfdj=43, dtinit=39,&
+ d0init=40, epslon=19, eta0=42, fuzz=45, huberc=48,&
+ incfac=23, lmax0=35, lmaxs=36, phmnfc=20, phmxfc=21,&
+ rdfcmn=24, rdfcmx=25, rfctol=32, rlimit=46, rsptol=49,&
+ sctol=37, sigmin=50, tuner1=26, tuner2=27, tuner3=28,&
+ tuner4=29, tuner5=30, xctol=33, xftol=34
+!/
+!
+!------------------------------- body --------------------------------
+!
+ machep = rmdcon(3)
+ v(afctol) = 1.d-20
+ if (machep .gt. 1.d-10) v(afctol) = machep**2
+ v(decfac) = 0.5d+0
+ sqteps = rmdcon(4)
+ v(dfac) = 0.6d+0
+ v(delta0) = sqteps
+ v(dtinit) = 1.d-6
+ mepcrt = machep ** (one/three)
+ v(d0init) = 1.d+0
+ v(epslon) = 0.1d+0
+ v(incfac) = 2.d+0
+ v(lmax0) = 1.d+0
+ v(lmaxs) = 1.d+0
+ v(phmnfc) = -0.1d+0
+ v(phmxfc) = 0.1d+0
+ v(rdfcmn) = 0.1d+0
+ v(rdfcmx) = 4.d+0
+ v(rfctol) = dmax1(1.d-10, mepcrt**2)
+ v(sctol) = v(rfctol)
+ v(tuner1) = 0.1d+0
+ v(tuner2) = 1.d-4
+ v(tuner3) = 0.75d+0
+ v(tuner4) = 0.5d+0
+ v(tuner5) = 0.75d+0
+ v(xctol) = sqteps
+ v(xftol) = 1.d+2 * machep
+!
+ if (alg .ge. 2) go to 10
+!
+! *** regression values
+!
+ v(cosmin) = dmax1(1.d-6, 1.d+2 * machep)
+ v(dinit) = 0.d+0
+ v(dltfdc) = mepcrt
+ v(dltfdj) = sqteps
+ v(fuzz) = 1.5d+0
+ v(huberc) = 0.7d+0
+ v(rlimit) = rmdcon(5)
+ v(rsptol) = 1.d-3
+ v(sigmin) = 1.d-4
+ go to 999
+!
+! *** general optimization values
+!
+ 10 v(bias) = 0.8d+0
+ v(dinit) = -1.0d+0
+ v(eta0) = 1.0d+3 * machep
+!
+ 999 return
+! *** last card of vdflt follows ***
+ end subroutine vdflt
+!-----------------------------------------------------------------------------
+ subroutine vscopy(p, y, s)
+!
+! *** set p-vector y to scalar s ***
+!
+ integer :: p
+ real(kind=8) :: s, y(p)
+!
+ integer :: i
+!
+ do 10 i = 1, p
+ 10 y(i) = s
+ return
+ end subroutine vscopy
+!-----------------------------------------------------------------------------
+ real(kind=8) function v2norm(p, x)
+!
+! *** return the 2-norm of the p-vector x, taking ***
+! *** care to avoid the most likely underflows. ***
+!
+ integer :: p
+ real(kind=8) :: x(p)
+!
+ integer :: i, j
+ real(kind=8) :: r, scale, sqteta, t, xi !el, one, zero
+!/+
+!el real(kind=8) :: dabs, dsqrt
+!/
+!el external rmdcon
+!el real(kind=8) :: rmdcon
+!
+!/6
+! data one/1.d+0/, zero/0.d+0/
+!/7
+ real(kind=8),parameter :: one=1.d+0, zero=0.d+0
+ save sqteta
+!/
+ data sqteta/0.d+0/
+!
+ if (p .gt. 0) go to 10
+ v2norm = zero
+ go to 999
+ 10 do 20 i = 1, p
+ if (x(i) .ne. zero) go to 30
+ 20 continue
+ v2norm = zero
+ go to 999
+!
+ 30 scale = dabs(x(i))
+ if (i .lt. p) go to 40
+ v2norm = scale
+ go to 999
+ 40 t = one
+ if (sqteta .eq. zero) sqteta = rmdcon(2)
+!
+! *** sqteta is (slightly larger than) the square root of the
+! *** smallest positive floating point number on the machine.
+! *** the tests involving sqteta are done to prevent underflows.
+!
+ j = i + 1
+ do 60 i = j, p
+ xi = dabs(x(i))
+ if (xi .gt. scale) go to 50
+ r = xi / scale
+ if (r .gt. sqteta) t = t + r*r
+ go to 60
+ 50 r = scale / xi
+ if (r .le. sqteta) r = zero
+ t = one + t * r*r
+ scale = xi
+ 60 continue
+!
+ v2norm = scale * dsqrt(t)
+ 999 return
+! *** last card of v2norm follows ***
+ end function v2norm
+!-----------------------------------------------------------------------------
+ subroutine humsl(n,d,x,calcf,calcgh,iv,liv,lv,v,uiparm,urparm,ufparm)
+!
+! *** minimize general unconstrained objective function using ***
+! *** (analytic) gradient and hessian provided by the caller. ***
+!
+ integer :: liv, lv, n
+ integer :: iv(liv), uiparm(1)
+ real(kind=8) :: d(n), x(n), v(lv), urparm(1)
+ real(kind=8),external :: ufparm
+! dimension v(78 + n*(n+12)), uiparm(*), urparm(*)
+ external :: calcf, calcgh
+!
+!------------------------------ discussion ---------------------------
+!
+! this routine is like sumsl, except that the subroutine para-
+! meter calcg of sumsl (which computes the gradient of the objec-
+! tive function) is replaced by the subroutine parameter calcgh,
+! which computes both the gradient and (lower triangle of the)
+! hessian of the objective function. the calling sequence is...
+! call calcgh(n, x, nf, g, h, uiparm, urparm, ufparm)
+! parameters n, x, nf, g, uiparm, urparm, and ufparm are the same
+! as for sumsl, while h is an array of length n*(n+1)/2 in which
+! calcgh must store the lower triangle of the hessian at x. start-
+! ing at h(1), calcgh must store the hessian entries in the order
+! (1,1), (2,1), (2,2), (3,1), (3,2), (3,3), ...
+! the value printed (by itsum) in the column labelled stppar
+! is the levenberg-marquardt used in computing the current step.
+! zero means a full newton step. if the special case described in
+! ref. 1 is detected, then stppar is negated. the value printed
+! in the column labelled npreldf is zero if the current hessian
+! is not positive definite.
+! it sometimes proves worthwhile to let d be determined from the
+! diagonal of the hessian matrix by setting iv(dtype) = 1 and
+! v(dinit) = 0. the following iv and v components are relevant...
+!
+! iv(dtol)..... iv(59) gives the starting subscript in v of the dtol
+! array used when d is updated. (iv(dtol) can be
+! initialized by calling humsl with iv(1) = 13.)
+! iv(dtype).... iv(16) tells how the scale vector d should be chosen.
+! iv(dtype) .le. 0 means that d should not be updated, and
+! iv(dtype) .ge. 1 means that d should be updated as
+! described below with v(dfac). default = 0.
+! v(dfac)..... v(41) and the dtol and d0 arrays (see v(dtinit) and
+! v(d0init)) are used in updating the scale vector d when
+! iv(dtype) .gt. 0. (d is initialized according to
+! v(dinit), described in sumsl.) let
+! d1(i) = max(sqrt(abs(h(i,i))), v(dfac)*d(i)),
+! where h(i,i) is the i-th diagonal element of the current
+! hessian. if iv(dtype) = 1, then d(i) is set to d1(i)
+! unless d1(i) .lt. dtol(i), in which case d(i) is set to
+! max(d0(i), dtol(i)).
+! if iv(dtype) .ge. 2, then d is updated during the first
+! iteration as for iv(dtype) = 1 (after any initialization
+! due to v(dinit)) and is left unchanged thereafter.
+! default = 0.6.
+! v(dtinit)... v(39), if positive, is the value to which all components
+! of the dtol array (see v(dfac)) are initialized. if
+! v(dtinit) = 0, then it is assumed that the caller has
+! stored dtol in v starting at v(iv(dtol)).
+! default = 10**-6.
+! v(d0init)... v(40), if positive, is the value to which all components
+! of the d0 vector (see v(dfac)) are initialized. if
+! v(dfac) = 0, then it is assumed that the caller has
+! stored d0 in v starting at v(iv(dtol)+n). default = 1.0.
+!
+! *** reference ***
+!
+! 1. gay, d.m. (1981), computing optimal locally constrained steps,
+! siam j. sci. statist. comput. 2, pp. 186-197.
+!.
+! *** general ***
+!
+! coded by david m. gay (winter 1980). revised sept. 1982.
+! this subroutine was written in connection with research supported
+! in part by the national science foundation under grants
+! mcs-7600324 and mcs-7906671.
+!
+!---------------------------- declarations ---------------------------
+!
+!el external deflt, humit
+!
+! deflt... provides default input values for iv and v.
+! humit... reverse-communication routine that does humsl algorithm.
+!
+ integer :: g1, h1, iv1, lh, nf
+ real(kind=8) :: f
+!
+! *** subscripts for iv ***
+!
+!el integer g, h, nextv, nfcall, nfgcal, toobig, vneed
+!
+!/6
+! data nextv/47/, nfcall/6/, nfgcal/7/, g/28/, h/56/, toobig/2/,
+! 1 vneed/4/
+!/7
+ integer,parameter :: nextv=47, nfcall=6, nfgcal=7, g=28, h=56,&
+ toobig=2,vneed=4
+!/
+!
+!+++++++++++++++++++++++++++++++ body ++++++++++++++++++++++++++++++++
+!
+ lh = n * (n + 1) / 2
+ if (iv(1) .eq. 0) call deflt(2, iv, liv, lv, v)
+ if (iv(1) .eq. 12 .or. iv(1) .eq. 13) &
+ iv(vneed) = iv(vneed) + n*(n+3)/2
+ iv1 = iv(1)
+ if (iv1 .eq. 14) go to 10
+ if (iv1 .gt. 2 .and. iv1 .lt. 12) go to 10
+ g1 = 1
+ h1 = 1
+ if (iv1 .eq. 12) iv(1) = 13
+ go to 20
+!
+ 10 g1 = iv(g)
+ h1 = iv(h)
+!
+ 20 call humit(d, f, v(g1), v(h1), iv, lh, liv, lv, n, v, x)
+ if (iv(1) - 2) 30, 40, 50
+!
+ 30 nf = iv(nfcall)
+ call calcf(n, x, nf, f, uiparm, urparm, ufparm)
+ if (nf .le. 0) iv(toobig) = 1
+ go to 20
+!
+ 40 call calcgh(n, x, iv(nfgcal), v(g1), v(h1), uiparm, urparm,&
+ ufparm)
+ go to 20
+!
+ 50 if (iv(1) .ne. 14) go to 999
+!
+! *** storage allocation
+!
+ iv(g) = iv(nextv)
+ iv(h) = iv(g) + n
+ iv(nextv) = iv(h) + n*(n+1)/2
+ if (iv1 .ne. 13) go to 10
+!
+ 999 return
+! *** last card of humsl follows ***
+ end subroutine humsl
+!-----------------------------------------------------------------------------
+ subroutine humit(d, fx, g, h, iv, lh, liv, lv, n, v, x)
+!
+! *** carry out humsl (unconstrained minimization) iterations, using
+! *** hessian matrix provided by the caller.
+!
+!el use control
+ use control, only:stopx
+
+! *** parameter declarations ***
+!
+ integer :: lh, liv, lv, n
+ integer :: iv(liv)
+ real(kind=8) :: d(n), fx, g(n), h(lh), v(lv), x(n)
+!
+!-------------------------- parameter usage --------------------------
+!
+! d.... scale vector.
+! fx... function value.
+! g.... gradient vector.
+! h.... lower triangle of the hessian, stored rowwise.
+! iv... integer value array.
+! lh... length of h = p*(p+1)/2.
+! liv.. length of iv (at least 60).
+! lv... length of v (at least 78 + n*(n+21)/2).
+! n.... number of variables (components in x and g).
+! v.... floating-point value array.
+! x.... parameter vector.
+!
+! *** discussion ***
+!
+! parameters iv, n, v, and x are the same as the corresponding
+! ones to humsl (which see), except that v can be shorter (since
+! the part of v that humsl uses for storing g and h is not needed).
+! moreover, compared with humsl, iv(1) may have the two additional
+! output values 1 and 2, which are explained below, as is the use
+! of iv(toobig) and iv(nfgcal). the value iv(g), which is an
+! output value from humsl, is not referenced by humit or the
+! subroutines it calls.
+!
+! iv(1) = 1 means the caller should set fx to f(x), the function value
+! at x, and call humit again, having changed none of the
+! other parameters. an exception occurs if f(x) cannot be
+! computed (e.g. if overflow would occur), which may happen
+! because of an oversized step. in this case the caller
+! should set iv(toobig) = iv(2) to 1, which will cause
+! humit to ignore fx and try a smaller step. the para-
+! meter nf that humsl passes to calcf (for possible use by
+! calcgh) is a copy of iv(nfcall) = iv(6).
+! iv(1) = 2 means the caller should set g to g(x), the gradient of f at
+! x, and h to the lower triangle of h(x), the hessian of f
+! at x, and call humit again, having changed none of the
+! other parameters except perhaps the scale vector d.
+! the parameter nf that humsl passes to calcg is
+! iv(nfgcal) = iv(7). if g(x) and h(x) cannot be evaluated,
+! then the caller may set iv(nfgcal) to 0, in which case
+! humit will return with iv(1) = 65.
+! note -- humit overwrites h with the lower triangle
+! of diag(d)**-1 * h(x) * diag(d)**-1.
+!.
+! *** general ***
+!
+! coded by david m. gay (winter 1980). revised sept. 1982.
+! this subroutine was written in connection with research supported
+! in part by the national science foundation under grants
+! mcs-7600324 and mcs-7906671.
+!
+! (see sumsl and humsl for references.)
+!
+!+++++++++++++++++++++++++++ declarations ++++++++++++++++++++++++++++
+!
+! *** local variables ***
+!
+ integer :: dg1, dummy, i, j, k, l, lstgst, nn1o2, step1,&
+ temp1, w1, x01
+ real(kind=8) :: t
+!
+! *** constants ***
+!
+!el real(kind=8) :: one, onep2, zero
+!
+! *** no intrinsic functions ***
+!
+! *** external functions and subroutines ***
+!
+!el external assst, deflt, dotprd, dupdu, gqtst, itsum, parck,
+!el 1 reldst, slvmul, stopx, vaxpy, vcopy, vscopy, v2norm
+!el logical stopx
+!el real(kind=8) :: dotprd, reldst, v2norm
+!
+! assst.... assesses candidate step.
+! deflt.... provides default iv and v input values.
+! dotprd... returns inner product of two vectors.
+! dupdu.... updates scale vector d.
+! gqtst.... computes optimally locally constrained step.
+! itsum.... prints iteration summary and info on initial and final x.
+! parck.... checks validity of input iv and v values.
+! reldst... computes v(reldx) = relative step size.
+! slvmul... multiplies symmetric matrix times vector, given the lower
+! triangle of the matrix.
+! stopx.... returns .true. if the break key has been pressed.
+! vaxpy.... computes scalar times one vector plus another.
+! vcopy.... copies one vector to another.
+! vscopy... sets all elements of a vector to a scalar.
+! v2norm... returns the 2-norm of a vector.
+!
+! *** subscripts for iv and v ***
+!
+!el integer cnvcod, dg, dgnorm, dinit, dstnrm, dtinit, dtol,
+!el 1 dtype, d0init, f, f0, fdif, gtstep, incfac, irc, kagqt,
+!el 2 lmat, lmax0, lmaxs, mode, model, mxfcal, mxiter, nextv,
+!el 3 nfcall, nfgcal, ngcall, niter, preduc, radfac, radinc,
+!el 4 radius, rad0, reldx, restor, step, stglim, stlstg, stppar,
+!el 5 toobig, tuner4, tuner5, vneed, w, xirc, x0
+!
+! *** iv subscript values ***
+!
+!/6
+! data cnvcod/55/, dg/37/, dtol/59/, dtype/16/, irc/29/, kagqt/33/,
+! 1 lmat/42/, mode/35/, model/5/, mxfcal/17/, mxiter/18/,
+! 2 nextv/47/, nfcall/6/, nfgcal/7/, ngcall/30/, niter/31/,
+! 3 radinc/8/, restor/9/, step/40/, stglim/11/, stlstg/41/,
+! 4 toobig/2/, vneed/4/, w/34/, xirc/13/, x0/43/
+!/7
+ integer,parameter :: cnvcod=55, dg=37, dtol=59, dtype=16, irc=29, kagqt=33,&
+ lmat=42, mode=35, model=5, mxfcal=17, mxiter=18,&
+ nextv=47, nfcall=6, nfgcal=7, ngcall=30, niter=31,&
+ radinc=8, restor=9, step=40, stglim=11, stlstg=41,&
+ toobig=2, vneed=4, w=34, xirc=13, x0=43
+!/
+!
+! *** v subscript values ***
+!
+!/6
+! data dgnorm/1/, dinit/38/, dstnrm/2/, dtinit/39/, d0init/40/,
+! 1 f/10/, f0/13/, fdif/11/, gtstep/4/, incfac/23/, lmax0/35/,
+! 2 lmaxs/36/, preduc/7/, radfac/16/, radius/8/, rad0/9/,
+! 3 reldx/17/, stppar/5/, tuner4/29/, tuner5/30/
+!/7
+ integer,parameter :: dgnorm=1, dinit=38, dstnrm=2, dtinit=39, d0init=40,&
+ f=10, f0=13, fdif=11, gtstep=4, incfac=23, lmax0=35,&
+ lmaxs=36, preduc=7, radfac=16, radius=8, rad0=9,&
+ reldx=17, stppar=5, tuner4=29, tuner5=30
+!/
+!
+!/6
+! data one/1.d+0/, onep2/1.2d+0/, zero/0.d+0/
+!/7
+ real(kind=8),parameter :: one=1.d+0, onep2=1.2d+0, zero=0.d+0
+!/
+!
+!+++++++++++++++++++++++++++++++ body ++++++++++++++++++++++++++++++++
+!
+ i = iv(1)
+ if (i .eq. 1) go to 30
+ if (i .eq. 2) go to 40
+!
+! *** check validity of iv and v input values ***
+!
+ if (iv(1) .eq. 0) call deflt(2, iv, liv, lv, v)
+ if (iv(1) .eq. 12 .or. iv(1) .eq. 13) &
+ iv(vneed) = iv(vneed) + n*(n+21)/2 + 7
+ call parck(2, d, iv, liv, lv, n, v)
+ i = iv(1) - 2
+ if (i .gt. 12) go to 999
+ nn1o2 = n * (n + 1) / 2
+ if (lh .ge. nn1o2) go to (210,210,210,210,210,210,160,120,160,&
+ 10,10,20), i
+ iv(1) = 66
+ go to 350
+!
+! *** storage allocation ***
+!
+ 10 iv(dtol) = iv(lmat) + nn1o2
+ iv(x0) = iv(dtol) + 2*n
+ iv(step) = iv(x0) + n
+ iv(stlstg) = iv(step) + n
+ iv(dg) = iv(stlstg) + n
+ iv(w) = iv(dg) + n
+ iv(nextv) = iv(w) + 4*n + 7
+ if (iv(1) .ne. 13) go to 20
+ iv(1) = 14
+ go to 999
+!
+! *** initialization ***
+!
+ 20 iv(niter) = 0
+ iv(nfcall) = 1
+ iv(ngcall) = 1
+ iv(nfgcal) = 1
+ iv(mode) = -1
+ iv(model) = 1
+ iv(stglim) = 1
+ iv(toobig) = 0
+ iv(cnvcod) = 0
+ iv(radinc) = 0
+ v(rad0) = zero
+ v(stppar) = zero
+ if (v(dinit) .ge. zero) call vscopy(n, d, v(dinit))
+ k = iv(dtol)
+ if (v(dtinit) .gt. zero) call vscopy(n, v(k), v(dtinit))
+ k = k + n
+ if (v(d0init) .gt. zero) call vscopy(n, v(k), v(d0init))
+ iv(1) = 1
+ go to 999
+!
+ 30 v(f) = fx
+ if (iv(mode) .ge. 0) go to 210
+ iv(1) = 2
+ if (iv(toobig) .eq. 0) go to 999
+ iv(1) = 63
+ go to 350
+!
+! *** make sure gradient could be computed ***
+!
+ 40 if (iv(nfgcal) .ne. 0) go to 50
+ iv(1) = 65
+ go to 350
+!
+! *** update the scale vector d ***
+!
+ 50 dg1 = iv(dg)
+ if (iv(dtype) .le. 0) go to 70
+ k = dg1
+ j = 0
+ do 60 i = 1, n
+ j = j + i
+ v(k) = h(j)
+ k = k + 1
+ 60 continue
+ call dupdu(d, v(dg1), iv, liv, lv, n, v)
+!
+! *** compute scaled gradient and its norm ***
+!
+ 70 dg1 = iv(dg)
+ k = dg1
+ do 80 i = 1, n
+ v(k) = g(i) / d(i)
+ k = k + 1
+ 80 continue
+ v(dgnorm) = v2norm(n, v(dg1))
+!
+! *** compute scaled hessian ***
+!
+ k = 1
+ do 100 i = 1, n
+ t = one / d(i)
+ do 90 j = 1, i
+ h(k) = t * h(k) / d(j)
+ k = k + 1
+ 90 continue
+ 100 continue
+!
+ if (iv(cnvcod) .ne. 0) go to 340
+ if (iv(mode) .eq. 0) go to 300
+!
+! *** allow first step to have scaled 2-norm at most v(lmax0) ***
+!
+ v(radius) = v(lmax0)
+!
+ iv(mode) = 0
+!
+!
+!----------------------------- main loop -----------------------------
+!
+!
+! *** print iteration summary, check iteration limit ***
+!
+ 110 call itsum(d, g, iv, liv, lv, n, v, x)
+ 120 k = iv(niter)
+ if (k .lt. iv(mxiter)) go to 130
+ iv(1) = 10
+ go to 350
+!
+ 130 iv(niter) = k + 1
+!
+! *** initialize for start of next iteration ***
+!
+ dg1 = iv(dg)
+ x01 = iv(x0)
+ v(f0) = v(f)
+ iv(irc) = 4
+ iv(kagqt) = -1
+!
+! *** copy x to x0 ***
+!
+ call vcopy(n, v(x01), x)
+!
+! *** update radius ***
+!
+ if (k .eq. 0) go to 150
+ step1 = iv(step)
+ k = step1
+ do 140 i = 1, n
+ v(k) = d(i) * v(k)
+ k = k + 1
+ 140 continue
+ v(radius) = v(radfac) * v2norm(n, v(step1))
+!
+! *** check stopx and function evaluation limit ***
+!
+! AL 4/30/95
+ dummy=iv(nfcall)
+ 150 if (.not. stopx(dummy)) go to 170
+ iv(1) = 11
+ go to 180
+!
+! *** come here when restarting after func. eval. limit or stopx.
+!
+ 160 if (v(f) .ge. v(f0)) go to 170
+ v(radfac) = one
+ k = iv(niter)
+ go to 130
+!
+ 170 if (iv(nfcall) .lt. iv(mxfcal)) go to 190
+ iv(1) = 9
+ 180 if (v(f) .ge. v(f0)) go to 350
+!
+! *** in case of stopx or function evaluation limit with
+! *** improved v(f), evaluate the gradient at x.
+!
+ iv(cnvcod) = iv(1)
+ go to 290
+!
+!. . . . . . . . . . . . . compute candidate step . . . . . . . . . .
+!
+ 190 step1 = iv(step)
+ dg1 = iv(dg)
+ l = iv(lmat)
+ w1 = iv(w)
+ call gqtst(d, v(dg1), h, iv(kagqt), v(l), n, v(step1), v, v(w1))
+ if (iv(irc) .eq. 6) go to 210
+!
+! *** check whether evaluating f(x0 + step) looks worthwhile ***
+!
+ if (v(dstnrm) .le. zero) go to 210
+ if (iv(irc) .ne. 5) go to 200
+ if (v(radfac) .le. one) go to 200
+ if (v(preduc) .le. onep2 * v(fdif)) go to 210
+!
+! *** compute f(x0 + step) ***
+!
+ 200 x01 = iv(x0)
+ step1 = iv(step)
+ call vaxpy(n, x, one, v(step1), v(x01))
+ iv(nfcall) = iv(nfcall) + 1
+ iv(1) = 1
+ iv(toobig) = 0
+ go to 999
+!
+!. . . . . . . . . . . . . assess candidate step . . . . . . . . . . .
+!
+ 210 x01 = iv(x0)
+ v(reldx) = reldst(n, d, x, v(x01))
+ call assst(iv, liv, lv, v)
+ step1 = iv(step)
+ lstgst = iv(stlstg)
+ if (iv(restor) .eq. 1) call vcopy(n, x, v(x01))
+ if (iv(restor) .eq. 2) call vcopy(n, v(lstgst), v(step1))
+ if (iv(restor) .ne. 3) go to 220
+ call vcopy(n, v(step1), v(lstgst))
+ call vaxpy(n, x, one, v(step1), v(x01))
+ v(reldx) = reldst(n, d, x, v(x01))
+!
+ 220 k = iv(irc)
+ go to (230,260,260,260,230,240,250,250,250,250,250,250,330,300), k
+!
+! *** recompute step with new radius ***
+!
+ 230 v(radius) = v(radfac) * v(dstnrm)
+ go to 150
+!
+! *** compute step of length v(lmaxs) for singular convergence test.
+!
+ 240 v(radius) = v(lmaxs)
+ go to 190
+!
+! *** convergence or false convergence ***
+!
+ 250 iv(cnvcod) = k - 4
+ if (v(f) .ge. v(f0)) go to 340
+ if (iv(xirc) .eq. 14) go to 340
+ iv(xirc) = 14
+!
+!. . . . . . . . . . . . process acceptable step . . . . . . . . . . .
+!
+ 260 if (iv(irc) .ne. 3) go to 290
+ temp1 = lstgst
+!
+! *** prepare for gradient tests ***
+! *** set temp1 = hessian * step + g(x0)
+! *** = diag(d) * (h * step + g(x0))
+!
+! use x0 vector as temporary.
+ k = x01
+ do 270 i = 1, n
+ v(k) = d(i) * v(step1)
+ k = k + 1
+ step1 = step1 + 1
+ 270 continue
+ call slvmul(n, v(temp1), h, v(x01))
+ do 280 i = 1, n
+ v(temp1) = d(i) * v(temp1) + g(i)
+ temp1 = temp1 + 1
+ 280 continue
+!
+! *** compute gradient and hessian ***
+!
+ 290 iv(ngcall) = iv(ngcall) + 1
+ iv(1) = 2
+ go to 999
+!
+ 300 iv(1) = 2
+ if (iv(irc) .ne. 3) go to 110
+!
+! *** set v(radfac) by gradient tests ***
+!
+ temp1 = iv(stlstg)
+ step1 = iv(step)
+!
+! *** set temp1 = diag(d)**-1 * (hessian*step + (g(x0)-g(x))) ***
+!
+ k = temp1
+ do 310 i = 1, n
+ v(k) = (v(k) - g(i)) / d(i)
+ k = k + 1
+ 310 continue
+!
+! *** do gradient tests ***
+!
+ if (v2norm(n, v(temp1)) .le. v(dgnorm) * v(tuner4)) go to 320
+ if (dotprd(n, g, v(step1)) &
+ .ge. v(gtstep) * v(tuner5)) go to 110
+ 320 v(radfac) = v(incfac)
+ go to 110
+!
+!. . . . . . . . . . . . . . misc. details . . . . . . . . . . . . . .
+!
+! *** bad parameters to assess ***
+!
+ 330 iv(1) = 64
+ go to 350
+!
+! *** print summary of final iteration and other requested items ***
+!
+ 340 iv(1) = iv(cnvcod)
+ iv(cnvcod) = 0
+ 350 call itsum(d, g, iv, liv, lv, n, v, x)
+!
+ 999 return
+!
+! *** last card of humit follows ***
+ end subroutine humit
+!-----------------------------------------------------------------------------
+ subroutine dupdu(d, hdiag, iv, liv, lv, n, v)
+!
+! *** update scale vector d for humsl ***
+!
+! *** parameter declarations ***
+!
+ integer :: liv, lv, n
+ integer :: iv(liv)
+ real(kind=8) :: d(n), hdiag(n), v(lv)
+!
+! *** local variables ***
+!
+ integer :: dtoli, d0i, i
+ real(kind=8) :: t, vdfac
+!
+! *** intrinsic functions ***
+!/+
+!el real(kind=8) :: dabs, dmax1, dsqrt
+!/
+! *** subscripts for iv and v ***
+!
+!el integer :: dfac, dtol, dtype, niter
+!/6
+! data dfac/41/, dtol/59/, dtype/16/, niter/31/
+!/7
+ integer,parameter :: dfac=41, dtol=59, dtype=16, niter=31
+!/
+!
+!------------------------------- body --------------------------------
+!
+ i = iv(dtype)
+ if (i .eq. 1) go to 10
+ if (iv(niter) .gt. 0) go to 999
+!
+ 10 dtoli = iv(dtol)
+ d0i = dtoli + n
+ vdfac = v(dfac)
+ do 20 i = 1, n
+ t = dmax1(dsqrt(dabs(hdiag(i))), vdfac*d(i))
+ if (t .lt. v(dtoli)) t = dmax1(v(dtoli), v(d0i))
+ d(i) = t
+ dtoli = dtoli + 1
+ d0i = d0i + 1
+ 20 continue
+!
+ 999 return
+! *** last card of dupdu follows ***
+ end subroutine dupdu
+!-----------------------------------------------------------------------------
+ subroutine gqtst(d, dig, dihdi, ka, l, p, step, v, w)
+!
+! *** compute goldfeld-quandt-trotter step by more-hebden technique ***
+! *** (nl2sol version 2.2), modified a la more and sorensen ***
+!
+! *** parameter declarations ***
+!
+ integer :: ka, p
+!al real(kind=8) :: d(p), dig(p), dihdi(1), l(1), v(21), step(p),
+!al 1 w(1)
+ real(kind=8) :: d(p), dig(p), dihdi(p*(p+1)/2), l(p*(p+1)/2),&
+ v(21), step(p),w(4*p+7)
+! dimension dihdi(p*(p+1)/2), l(p*(p+1)/2), w(4*p+7)
+!
+!+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+!
+! *** purpose ***
+!
+! given the (compactly stored) lower triangle of a scaled
+! hessian (approximation) and a nonzero scaled gradient vector,
+! this subroutine computes a goldfeld-quandt-trotter step of
+! approximate length v(radius) by the more-hebden technique. in
+! other words, step is computed to (approximately) minimize
+! psi(step) = (g**t)*step + 0.5*(step**t)*h*step such that the
+! 2-norm of d*step is at most (approximately) v(radius), where
+! g is the gradient, h is the hessian, and d is a diagonal
+! scale matrix whose diagonal is stored in the parameter d.
+! (gqtst assumes dig = d**-1 * g and dihdi = d**-1 * h * d**-1.)
+!
+! *** parameter description ***
+!
+! d (in) = the scale vector, i.e. the diagonal of the scale
+! matrix d mentioned above under purpose.
+! dig (in) = the scaled gradient vector, d**-1 * g. if g = 0, then
+! step = 0 and v(stppar) = 0 are returned.
+! dihdi (in) = lower triangle of the scaled hessian (approximation),
+! i.e., d**-1 * h * d**-1, stored compactly by rows., i.e.,
+! in the order (1,1), (2,1), (2,2), (3,1), (3,2), etc.
+! ka (i/o) = the number of hebden iterations (so far) taken to deter-
+! mine step. ka .lt. 0 on input means this is the first
+! attempt to determine step (for the present dig and dihdi)
+! -- ka is initialized to 0 in this case. output with
+! ka = 0 (or v(stppar) = 0) means step = -(h**-1)*g.
+! l (i/o) = workspace of length p*(p+1)/2 for cholesky factors.
+! p (in) = number of parameters -- the hessian is a p x p matrix.
+! step (i/o) = the step computed.
+! v (i/o) contains various constants and variables described below.
+! w (i/o) = workspace of length 4*p + 6.
+!
+! *** entries in v ***
+!
+! v(dgnorm) (i/o) = 2-norm of (d**-1)*g.
+! v(dstnrm) (output) = 2-norm of d*step.
+! v(dst0) (i/o) = 2-norm of d*(h**-1)*g (for pos. def. h only), or
+! overestimate of smallest eigenvalue of (d**-1)*h*(d**-1).
+! v(epslon) (in) = max. rel. error allowed for psi(step). for the
+! step returned, psi(step) will exceed its optimal value
+! by less than -v(epslon)*psi(step). suggested value = 0.1.
+! v(gtstep) (out) = inner product between g and step.
+! v(nreduc) (out) = psi(-(h**-1)*g) = psi(newton step) (for pos. def.
+! h only -- v(nreduc) is set to zero otherwise).
+! v(phmnfc) (in) = tol. (together with v(phmxfc)) for accepting step
+! (more*s sigma). the error v(dstnrm) - v(radius) must lie
+! between v(phmnfc)*v(radius) and v(phmxfc)*v(radius).
+! v(phmxfc) (in) (see v(phmnfc).)
+! suggested values -- v(phmnfc) = -0.25, v(phmxfc) = 0.5.
+! v(preduc) (out) = psi(step) = predicted obj. func. reduction for step.
+! v(radius) (in) = radius of current (scaled) trust region.
+! v(rad0) (i/o) = value of v(radius) from previous call.
+! v(stppar) (i/o) is normally the marquardt parameter, i.e. the alpha
+! described below under algorithm notes. if h + alpha*d**2
+! (see algorithm notes) is (nearly) singular, however,
+! then v(stppar) = -alpha.
+!
+! *** usage notes ***
+!
+! if it is desired to recompute step using a different value of
+! v(radius), then this routine may be restarted by calling it
+! with all parameters unchanged except v(radius). (this explains
+! why step and w are listed as i/o). on an initial call (one with
+! ka .lt. 0), step and w need not be initialized and only compo-
+! nents v(epslon), v(stppar), v(phmnfc), v(phmxfc), v(radius), and
+! v(rad0) of v must be initialized.
+!
+! *** algorithm notes ***
+!
+! the desired g-q-t step (ref. 2, 3, 4, 6) satisfies
+! (h + alpha*d**2)*step = -g for some nonnegative alpha such that
+! h + alpha*d**2 is positive semidefinite. alpha and step are
+! computed by a scheme analogous to the one described in ref. 5.
+! estimates of the smallest and largest eigenvalues of the hessian
+! are obtained from the gerschgorin circle theorem enhanced by a
+! simple form of the scaling described in ref. 7. cases in which
+! h + alpha*d**2 is nearly (or exactly) singular are handled by
+! the technique discussed in ref. 2. in these cases, a step of
+! (exact) length v(radius) is returned for which psi(step) exceeds
+! its optimal value by less than -v(epslon)*psi(step). the test
+! suggested in ref. 6 for detecting the special case is performed
+! once two matrix factorizations have been done -- doing so sooner
+! seems to degrade the performance of optimization routines that
+! call this routine.
+!
+! *** functions and subroutines called ***
+!
+! dotprd - returns inner product of two vectors.
+! litvmu - applies inverse-transpose of compact lower triang. matrix.
+! livmul - applies inverse of compact lower triang. matrix.
+! lsqrt - finds cholesky factor (of compactly stored lower triang.).
+! lsvmin - returns approx. to min. sing. value of lower triang. matrix.
+! rmdcon - returns machine-dependent constants.
+! v2norm - returns 2-norm of a vector.
+!
+! *** references ***
+!
+! 1. dennis, j.e., gay, d.m., and welsch, r.e. (1981), an adaptive
+! nonlinear least-squares algorithm, acm trans. math.
+! software, vol. 7, no. 3.
+! 2. gay, d.m. (1981), computing optimal locally constrained steps,
+! siam j. sci. statist. computing, vol. 2, no. 2, pp.
+! 186-197.
+! 3. goldfeld, s.m., quandt, r.e., and trotter, h.f. (1966),
+! maximization by quadratic hill-climbing, econometrica 34,
+! pp. 541-551.
+! 4. hebden, m.d. (1973), an algorithm for minimization using exact
+! second derivatives, report t.p. 515, theoretical physics
+! div., a.e.r.e. harwell, oxon., england.
+! 5. more, j.j. (1978), the levenberg-marquardt algorithm, implemen-
+! tation and theory, pp.105-116 of springer lecture notes
+! in mathematics no. 630, edited by g.a. watson, springer-
+! verlag, berlin and new york.
+! 6. more, j.j., and sorensen, d.c. (1981), computing a trust region
+! step, technical report anl-81-83, argonne national lab.
+! 7. varga, r.s. (1965), minimal gerschgorin sets, pacific j. math. 15,
+! pp. 719-729.
+!
+! *** general ***
+!
+! coded by david m. gay.
+! this subroutine was written in connection with research
+! supported by the national science foundation under grants
+! mcs-7600324, dcr75-10143, 76-14311dss, mcs76-11989, and
+! mcs-7906671.
+!
+!+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+!
+! *** local variables ***
+!
+ logical :: restrt
+ integer :: dggdmx, diag, diag0, dstsav, emax, emin, i, im1, inc, irc,&
+ j, k, kalim, kamin, k1, lk0, phipin, q, q0, uk0, x
+ real(kind=8) :: alphak, aki, akk, delta, dst, eps, gtsta, lk,&
+ oldphi, phi, phimax, phimin, psifac, rad, radsq,&
+ root, si, sk, sw, t, twopsi, t1, t2, uk, wi
+!
+! *** constants ***
+ real(kind=8) :: big, dgxfac !el, epsfac, four, half, kappa, negone,
+!el 1 one, p001, six, three, two, zero
+!
+! *** intrinsic functions ***
+!/+
+!el real(kind=8) :: dabs, dmax1, dmin1, dsqrt
+!/
+! *** external functions and subroutines ***
+!
+!el external dotprd, litvmu, livmul, lsqrt, lsvmin, rmdcon, v2norm
+!el real(kind=8) :: dotprd, lsvmin, rmdcon, v2norm
+!
+! *** subscripts for v ***
+!
+!el integer dgnorm, dstnrm, dst0, epslon, gtstep, stppar, nreduc,
+!el 1 phmnfc, phmxfc, preduc, radius, rad0
+!/6
+! data dgnorm/1/, dstnrm/2/, dst0/3/, epslon/19/, gtstep/4/,
+! 1 nreduc/6/, phmnfc/20/, phmxfc/21/, preduc/7/, radius/8/,
+! 2 rad0/9/, stppar/5/
+!/7
+ integer,parameter :: dgnorm=1, dstnrm=2, dst0=3, epslon=19, gtstep=4,&
+ nreduc=6, phmnfc=20, phmxfc=21, preduc=7, radius=8,&
+ rad0=9, stppar=5
+!/
+!
+!/6
+! data epsfac/50.0d+0/, four/4.0d+0/, half/0.5d+0/,
+! 1 kappa/2.0d+0/, negone/-1.0d+0/, one/1.0d+0/, p001/1.0d-3/,
+! 2 six/6.0d+0/, three/3.0d+0/, two/2.0d+0/, zero/0.0d+0/
+!/7
+ real(kind=8), parameter :: epsfac=50.0d+0, four=4.0d+0, half=0.5d+0,&
+ kappa=2.0d+0, negone=-1.0d+0, one=1.0d+0, p001=1.0d-3,&
+ six=6.0d+0, three=3.0d+0, two=2.0d+0, zero=0.0d+0
+ save dgxfac
+!/
+ data big/0.d+0/, dgxfac/0.d+0/
+!
+! *** body ***
+!
+! *** store largest abs. entry in (d**-1)*h*(d**-1) at w(dggdmx).
+ dggdmx = p + 1
+! *** store gerschgorin over- and underestimates of the largest
+! *** and smallest eigenvalues of (d**-1)*h*(d**-1) at w(emax)
+! *** and w(emin) respectively.
+ emax = dggdmx + 1
+ emin = emax + 1
+! *** for use in recomputing step, the final values of lk, uk, dst,
+! *** and the inverse derivative of more*s phi at 0 (for pos. def.
+! *** h) are stored in w(lk0), w(uk0), w(dstsav), and w(phipin)
+! *** respectively.
+ lk0 = emin + 1
+ phipin = lk0 + 1
+ uk0 = phipin + 1
+ dstsav = uk0 + 1
+! *** store diag of (d**-1)*h*(d**-1) in w(diag),...,w(diag0+p).
+ diag0 = dstsav
+ diag = diag0 + 1
+! *** store -d*step in w(q),...,w(q0+p).
+ q0 = diag0 + p
+ q = q0 + 1
+! *** allocate storage for scratch vector x ***
+ x = q + p
+ rad = v(radius)
+ radsq = rad**2
+! *** phitol = max. error allowed in dst = v(dstnrm) = 2-norm of
+! *** d*step.
+ phimax = v(phmxfc) * rad
+ phimin = v(phmnfc) * rad
+ psifac = two * v(epslon) / (three * (four * (v(phmnfc) + one) * &
+ (kappa + one) + kappa + two) * rad**2)
+! *** oldphi is used to detect limits of numerical accuracy. if
+! *** we recompute step and it does not change, then we accept it.
+ oldphi = zero
+ eps = v(epslon)
+ irc = 0
+ restrt = .false.
+ kalim = ka + 50
+!
+! *** start or restart, depending on ka ***
+!
+ if (ka .ge. 0) go to 290
+!
+! *** fresh start ***
+!
+ k = 0
+ uk = negone
+ ka = 0
+ kalim = 50
+ v(dgnorm) = v2norm(p, dig)
+ v(nreduc) = zero
+ v(dst0) = zero
+ kamin = 3
+ if (v(dgnorm) .eq. zero) kamin = 0
+!
+! *** store diag(dihdi) in w(diag0+1),...,w(diag0+p) ***
+!
+ j = 0
+ do 10 i = 1, p
+ j = j + i
+ k1 = diag0 + i
+ w(k1) = dihdi(j)
+ 10 continue
+!
+! *** determine w(dggdmx), the largest element of dihdi ***
+!
+ t1 = zero
+ j = p * (p + 1) / 2
+ do 20 i = 1, j
+ t = dabs(dihdi(i))
+ if (t1 .lt. t) t1 = t
+ 20 continue
+ w(dggdmx) = t1
+!
+! *** try alpha = 0 ***
+!
+ 30 call lsqrt(1, p, l, dihdi, irc)
+ if (irc .eq. 0) go to 50
+! *** indef. h -- underestimate smallest eigenvalue, use this
+! *** estimate to initialize lower bound lk on alpha.
+ j = irc*(irc+1)/2
+ t = l(j)
+ l(j) = one
+ do 40 i = 1, irc
+ 40 w(i) = zero
+ w(irc) = one
+ call litvmu(irc, w, l, w)
+ t1 = v2norm(irc, w)
+ lk = -t / t1 / t1
+ v(dst0) = -lk
+ if (restrt) go to 210
+ go to 70
+!
+! *** positive definite h -- compute unmodified newton step. ***
+ 50 lk = zero
+ t = lsvmin(p, l, w(q), w(q))
+ if (t .ge. one) go to 60
+ if (big .le. zero) big = rmdcon(6)
+ if (v(dgnorm) .ge. t*t*big) go to 70
+ 60 call livmul(p, w(q), l, dig)
+ gtsta = dotprd(p, w(q), w(q))
+ v(nreduc) = half * gtsta
+ call litvmu(p, w(q), l, w(q))
+ dst = v2norm(p, w(q))
+ v(dst0) = dst
+ phi = dst - rad
+ if (phi .le. phimax) go to 260
+ if (restrt) go to 210
+!
+! *** prepare to compute gerschgorin estimates of largest (and
+! *** smallest) eigenvalues. ***
+!
+ 70 k = 0
+ do 100 i = 1, p
+ wi = zero
+ if (i .eq. 1) go to 90
+ im1 = i - 1
+ do 80 j = 1, im1
+ k = k + 1
+ t = dabs(dihdi(k))
+ wi = wi + t
+ w(j) = w(j) + t
+ 80 continue
+ 90 w(i) = wi
+ k = k + 1
+ 100 continue
+!
+! *** (under-)estimate smallest eigenvalue of (d**-1)*h*(d**-1) ***
+!
+ k = 1
+ t1 = w(diag) - w(1)
+ if (p .le. 1) go to 120
+ do 110 i = 2, p
+ j = diag0 + i
+ t = w(j) - w(i)
+ if (t .ge. t1) go to 110
+ t1 = t
+ k = i
+ 110 continue
+!
+ 120 sk = w(k)
+ j = diag0 + k
+ akk = w(j)
+ k1 = k*(k-1)/2 + 1
+ inc = 1
+ t = zero
+ do 150 i = 1, p
+ if (i .eq. k) go to 130
+ aki = dabs(dihdi(k1))
+ si = w(i)
+ j = diag0 + i
+ t1 = half * (akk - w(j) + si - aki)
+ t1 = t1 + dsqrt(t1*t1 + sk*aki)
+ if (t .lt. t1) t = t1
+ if (i .lt. k) go to 140
+ 130 inc = i
+ 140 k1 = k1 + inc
+ 150 continue
+!
+ w(emin) = akk - t
+ uk = v(dgnorm)/rad - w(emin)
+ if (v(dgnorm) .eq. zero) uk = uk + p001 + p001*uk
+ if (uk .le. zero) uk = p001
+!
+! *** compute gerschgorin (over-)estimate of largest eigenvalue ***
+!
+ k = 1
+ t1 = w(diag) + w(1)
+ if (p .le. 1) go to 170
+ do 160 i = 2, p
+ j = diag0 + i
+ t = w(j) + w(i)
+ if (t .le. t1) go to 160
+ t1 = t
+ k = i
+ 160 continue
+!
+ 170 sk = w(k)
+ j = diag0 + k
+ akk = w(j)
+ k1 = k*(k-1)/2 + 1
+ inc = 1
+ t = zero
+ do 200 i = 1, p
+ if (i .eq. k) go to 180
+ aki = dabs(dihdi(k1))
+ si = w(i)
+ j = diag0 + i
+ t1 = half * (w(j) + si - aki - akk)
+ t1 = t1 + dsqrt(t1*t1 + sk*aki)
+ if (t .lt. t1) t = t1
+ if (i .lt. k) go to 190
+ 180 inc = i
+ 190 k1 = k1 + inc
+ 200 continue
+!
+ w(emax) = akk + t
+ lk = dmax1(lk, v(dgnorm)/rad - w(emax))
+!
+! *** alphak = current value of alpha (see alg. notes above). we
+! *** use more*s scheme for initializing it.
+ alphak = dabs(v(stppar)) * v(rad0)/rad
+!
+ if (irc .ne. 0) go to 210
+!
+! *** compute l0 for positive definite h ***
+!
+ call livmul(p, w, l, w(q))
+ t = v2norm(p, w)
+ w(phipin) = dst / t / t
+ lk = dmax1(lk, phi*w(phipin))
+!
+! *** safeguard alphak and add alphak*i to (d**-1)*h*(d**-1) ***
+!
+ 210 ka = ka + 1
+ if (-v(dst0) .ge. alphak .or. alphak .lt. lk .or. alphak .ge. uk) &
+ alphak = uk * dmax1(p001, dsqrt(lk/uk))
+ if (alphak .le. zero) alphak = half * uk
+ if (alphak .le. zero) alphak = uk
+ k = 0
+ do 220 i = 1, p
+ k = k + i
+ j = diag0 + i
+ dihdi(k) = w(j) + alphak
+ 220 continue
+!
+! *** try computing cholesky decomposition ***
+!
+ call lsqrt(1, p, l, dihdi, irc)
+ if (irc .eq. 0) go to 240
+!
+! *** (d**-1)*h*(d**-1) + alphak*i is indefinite -- overestimate
+! *** smallest eigenvalue for use in updating lk ***
+!
+ j = (irc*(irc+1))/2
+ t = l(j)
+ l(j) = one
+ do 230 i = 1, irc
+ 230 w(i) = zero
+ w(irc) = one
+ call litvmu(irc, w, l, w)
+ t1 = v2norm(irc, w)
+ lk = alphak - t/t1/t1
+ v(dst0) = -lk
+ go to 210
+!
+! *** alphak makes (d**-1)*h*(d**-1) positive definite.
+! *** compute q = -d*step, check for convergence. ***
+!
+ 240 call livmul(p, w(q), l, dig)
+ gtsta = dotprd(p, w(q), w(q))
+ call litvmu(p, w(q), l, w(q))
+ dst = v2norm(p, w(q))
+ phi = dst - rad
+ if (phi .le. phimax .and. phi .ge. phimin) go to 270
+ if (phi .eq. oldphi) go to 270
+ oldphi = phi
+ if (phi .lt. zero) go to 330
+!
+! *** unacceptable alphak -- update lk, uk, alphak ***
+!
+ 250 if (ka .ge. kalim) go to 270
+! *** the following dmin1 is necessary because of restarts ***
+ if (phi .lt. zero) uk = dmin1(uk, alphak)
+! *** kamin = 0 only iff the gradient vanishes ***
+ if (kamin .eq. 0) go to 210
+ call livmul(p, w, l, w(q))
+ t1 = v2norm(p, w)
+ alphak = alphak + (phi/t1) * (dst/t1) * (dst/rad)
+ lk = dmax1(lk, alphak)
+ go to 210
+!
+! *** acceptable step on first try ***
+!
+ 260 alphak = zero
+!
+! *** successful step in general. compute step = -(d**-1)*q ***
+!
+ 270 do 280 i = 1, p
+ j = q0 + i
+ step(i) = -w(j)/d(i)
+ 280 continue
+ v(gtstep) = -gtsta
+ v(preduc) = half * (dabs(alphak)*dst*dst + gtsta)
+ go to 410
+!
+!
+! *** restart with new radius ***
+!
+ 290 if (v(dst0) .le. zero .or. v(dst0) - rad .gt. phimax) go to 310
+!
+! *** prepare to return newton step ***
+!
+ restrt = .true.
+ ka = ka + 1
+ k = 0
+ do 300 i = 1, p
+ k = k + i
+ j = diag0 + i
+ dihdi(k) = w(j)
+ 300 continue
+ uk = negone
+ go to 30
+!
+ 310 kamin = ka + 3
+ if (v(dgnorm) .eq. zero) kamin = 0
+ if (ka .eq. 0) go to 50
+!
+ dst = w(dstsav)
+ alphak = dabs(v(stppar))
+ phi = dst - rad
+ t = v(dgnorm)/rad
+ uk = t - w(emin)
+ if (v(dgnorm) .eq. zero) uk = uk + p001 + p001*uk
+ if (uk .le. zero) uk = p001
+ if (rad .gt. v(rad0)) go to 320
+!
+! *** smaller radius ***
+ lk = zero
+ if (alphak .gt. zero) lk = w(lk0)
+ lk = dmax1(lk, t - w(emax))
+ if (v(dst0) .gt. zero) lk = dmax1(lk, (v(dst0)-rad)*w(phipin))
+ go to 250
+!
+! *** bigger radius ***
+ 320 if (alphak .gt. zero) uk = dmin1(uk, w(uk0))
+ lk = dmax1(zero, -v(dst0), t - w(emax))
+ if (v(dst0) .gt. zero) lk = dmax1(lk, (v(dst0)-rad)*w(phipin))
+ go to 250
+!
+! *** decide whether to check for special case... in practice (from
+! *** the standpoint of the calling optimization code) it seems best
+! *** not to check until a few iterations have failed -- hence the
+! *** test on kamin below.
+!
+ 330 delta = alphak + dmin1(zero, v(dst0))
+ twopsi = alphak*dst*dst + gtsta
+ if (ka .ge. kamin) go to 340
+! *** if the test in ref. 2 is satisfied, fall through to handle
+! *** the special case (as soon as the more-sorensen test detects
+! *** it).
+ if (delta .ge. psifac*twopsi) go to 370
+!
+! *** check for the special case of h + alpha*d**2 (nearly)
+! *** singular. use one step of inverse power method with start
+! *** from lsvmin to obtain approximate eigenvector corresponding
+! *** to smallest eigenvalue of (d**-1)*h*(d**-1). lsvmin returns
+! *** x and w with l*w = x.
+!
+ 340 t = lsvmin(p, l, w(x), w)
+!
+! *** normalize w ***
+ do 350 i = 1, p
+ 350 w(i) = t*w(i)
+! *** complete current inv. power iter. -- replace w by (l**-t)*w.
+ call litvmu(p, w, l, w)
+ t2 = one/v2norm(p, w)
+ do 360 i = 1, p
+ 360 w(i) = t2*w(i)
+ t = t2 * t
+!
+! *** now w is the desired approximate (unit) eigenvector and
+! *** t*x = ((d**-1)*h*(d**-1) + alphak*i)*w.
+!
+ sw = dotprd(p, w(q), w)
+ t1 = (rad + dst) * (rad - dst)
+ root = dsqrt(sw*sw + t1)
+ if (sw .lt. zero) root = -root
+ si = t1 / (sw + root)
+!
+! *** the actual test for the special case...
+!
+ if ((t2*si)**2 .le. eps*(dst**2 + alphak*radsq)) go to 380
+!
+! *** update upper bound on smallest eigenvalue (when not positive)
+! *** (as recommended by more and sorensen) and continue...
+!
+ if (v(dst0) .le. zero) v(dst0) = dmin1(v(dst0), t2**2 - alphak)
+ lk = dmax1(lk, -v(dst0))
+!
+! *** check whether we can hope to detect the special case in
+! *** the available arithmetic. accept step as it is if not.
+!
+! *** if not yet available, obtain machine dependent value dgxfac.
+ 370 if (dgxfac .eq. zero) dgxfac = epsfac * rmdcon(3)
+!
+ if (delta .gt. dgxfac*w(dggdmx)) go to 250
+ go to 270
+!
+! *** special case detected... negate alphak to indicate special case
+!
+ 380 alphak = -alphak
+ v(preduc) = half * twopsi
+!
+! *** accept current step if adding si*w would lead to a
+! *** further relative reduction in psi of less than v(epslon)/3.
+!
+ t1 = zero
+ t = si*(alphak*sw - half*si*(alphak + t*dotprd(p,w(x),w)))
+ if (t .lt. eps*twopsi/six) go to 390
+ v(preduc) = v(preduc) + t
+ dst = rad
+ t1 = -si
+ 390 do 400 i = 1, p
+ j = q0 + i
+ w(j) = t1*w(i) - w(j)
+ step(i) = w(j) / d(i)
+ 400 continue
+ v(gtstep) = dotprd(p, dig, w(q))
+!
+! *** save values for use in a possible restart ***
+!
+ 410 v(dstnrm) = dst
+ v(stppar) = alphak
+ w(lk0) = lk
+ w(uk0) = uk
+ v(rad0) = rad
+ w(dstsav) = dst
+!
+! *** restore diagonal of dihdi ***
+!
+ j = 0
+ do 420 i = 1, p
+ j = j + i
+ k = diag0 + i
+ dihdi(j) = w(k)
+ 420 continue
+!
+ 999 return
+!
+! *** last card of gqtst follows ***
+ end subroutine gqtst
+!-----------------------------------------------------------------------------
+ subroutine lsqrt(n1, n, l, a, irc)
+!
+! *** compute rows n1 through n of the cholesky factor l of
+! *** a = l*(l**t), where l and the lower triangle of a are both
+! *** stored compactly by rows (and may occupy the same storage).
+! *** irc = 0 means all went well. irc = j means the leading
+! *** principal j x j submatrix of a is not positive definite --
+! *** and l(j*(j+1)/2) contains the (nonpos.) reduced j-th diagonal.
+!
+! *** parameters ***
+!
+ integer :: n1, n, irc
+!al real(kind=8) :: l(1), a(1)
+ real(kind=8) :: l(n*(n+1)/2), a(n*(n+1)/2)
+! dimension l(n*(n+1)/2), a(n*(n+1)/2)
+!
+! *** local variables ***
+!
+ integer :: i, ij, ik, im1, i0, j, jk, jm1, j0, k
+ real(kind=8) :: t, td !el, zero
+!
+! *** intrinsic functions ***
+!/+
+!el real(kind=8) :: dsqrt
+!/
+!/6
+! data zero/0.d+0/
+!/7
+ real(kind=8),parameter :: zero=0.d+0
+!/
+!
+! *** body ***
+!
+ i0 = n1 * (n1 - 1) / 2
+ do 50 i = n1, n
+ td = zero
+ if (i .eq. 1) go to 40
+ j0 = 0
+ im1 = i - 1
+ do 30 j = 1, im1
+ t = zero
+ if (j .eq. 1) go to 20
+ jm1 = j - 1
+ do 10 k = 1, jm1
+ ik = i0 + k
+ jk = j0 + k
+ t = t + l(ik)*l(jk)
+ 10 continue
+ 20 ij = i0 + j
+ j0 = j0 + j
+ t = (a(ij) - t) / l(j0)
+ l(ij) = t
+ td = td + t*t
+ 30 continue
+ 40 i0 = i0 + i
+ t = a(i0) - td
+ if (t .le. zero) go to 60
+ l(i0) = dsqrt(t)
+ 50 continue
+!
+ irc = 0
+ go to 999
+!
+ 60 l(i0) = t
+ irc = i
+!
+ 999 return
+!
+! *** last card of lsqrt ***
+ end subroutine lsqrt
+!-----------------------------------------------------------------------------
+ real(kind=8) function lsvmin(p, l, x, y)
+!
+! *** estimate smallest sing. value of packed lower triang. matrix l
+!
+! *** parameter declarations ***
+!
+ integer :: p
+!al real(kind=8) :: l(1), x(p), y(p)
+ real(kind=8) :: l(p*(p+1)/2), x(p), y(p)
+! dimension l(p*(p+1)/2)
+!
+!+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+!
+! *** purpose ***
+!
+! this function returns a good over-estimate of the smallest
+! singular value of the packed lower triangular matrix l.
+!
+! *** parameter description ***
+!
+! p (in) = the order of l. l is a p x p lower triangular matrix.
+! l (in) = array holding the elements of l in row order, i.e.
+! l(1,1), l(2,1), l(2,2), l(3,1), l(3,2), l(3,3), etc.
+! x (out) if lsvmin returns a positive value, then x is a normalized
+! approximate left singular vector corresponding to the
+! smallest singular value. this approximation may be very
+! crude. if lsvmin returns zero, then some components of x
+! are zero and the rest retain their input values.
+! y (out) if lsvmin returns a positive value, then y = (l**-1)*x is an
+! unnormalized approximate right singular vector correspond-
+! ing to the smallest singular value. this approximation
+! may be crude. if lsvmin returns zero, then y retains its
+! input value. the caller may pass the same vector for x
+! and y (nonstandard fortran usage), in which case y over-
+! writes x (for nonzero lsvmin returns).
+!
+! *** algorithm notes ***
+!
+! the algorithm is based on (1), with the additional provision that
+! lsvmin = 0 is returned if the smallest diagonal element of l
+! (in magnitude) is not more than the unit roundoff times the
+! largest. the algorithm uses a random number generator proposed
+! in (4), which passes the spectral test with flying colors -- see
+! (2) and (3).
+!
+! *** subroutines and functions called ***
+!
+! v2norm - function, returns the 2-norm of a vector.
+!
+! *** references ***
+!
+! (1) cline, a., moler, c., stewart, g., and wilkinson, j.h.(1977),
+! an estimate for the condition number of a matrix, report
+! tm-310, applied math. div., argonne national laboratory.
+!
+! (2) hoaglin, d.c. (1976), theoretical properties of congruential
+! random-number generators -- an empirical view,
+! memorandum ns-340, dept. of statistics, harvard univ.
+!
+! (3) knuth, d.e. (1969), the art of computer programming, vol. 2
+! (seminumerical algorithms), addison-wesley, reading, mass.
+!
+! (4) smith, c.s. (1971), multiplicative pseudo-random number
+! generators with prime modulus, j. assoc. comput. mach. 18,
+! pp. 586-593.
+!
+! *** history ***
+!
+! designed and coded by david m. gay (winter 1977/summer 1978).
+!
+! *** general ***
+!
+! this subroutine was written in connection with research
+! supported by the national science foundation under grants
+! mcs-7600324, dcr75-10143, 76-14311dss, and mcs76-11989.
+!
+!+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+!
+! *** local variables ***
+!
+ integer :: i, ii, ix, j, ji, jj, jjj, jm1, j0, pm1
+ real(kind=8) :: b, sminus, splus, t, xminus, xplus
+!
+! *** constants ***
+!
+!el real(kind=8) :: half, one, r9973, zero
+!
+! *** intrinsic functions ***
+!/+
+!el integer mod
+!el real float
+!el real(kind=8) :: dabs
+!/
+! *** external functions and subroutines ***
+!
+!el external dotprd, v2norm, vaxpy
+!el real(kind=8) :: dotprd, v2norm
+!
+!/6
+! data half/0.5d+0/, one/1.d+0/, r9973/9973.d+0/, zero/0.d+0/
+!/7
+ real(kind=8),parameter :: half=0.5d+0, one=1.d+0, r9973=9973.d+0, zero=0.d+0
+!/
+!
+! *** body ***
+!
+ ix = 2
+ pm1 = p - 1
+!
+! *** first check whether to return lsvmin = 0 and initialize x ***
+!
+ ii = 0
+ j0 = p*pm1/2
+ jj = j0 + p
+ if (l(jj) .eq. zero) go to 110
+ ix = mod(3432*ix, 9973)
+ b = half*(one + float(ix)/r9973)
+ xplus = b / l(jj)
+ x(p) = xplus
+ if (p .le. 1) go to 60
+ do 10 i = 1, pm1
+ ii = ii + i
+ if (l(ii) .eq. zero) go to 110
+ ji = j0 + i
+ x(i) = xplus * l(ji)
+ 10 continue
+!
+! *** solve (l**t)*x = b, where the components of b have randomly
+! *** chosen magnitudes in (.5,1) with signs chosen to make x large.
+!
+! do j = p-1 to 1 by -1...
+ do 50 jjj = 1, pm1
+ j = p - jjj
+! *** determine x(j) in this iteration. note for i = 1,2,...,j
+! *** that x(i) holds the current partial sum for row i.
+ ix = mod(3432*ix, 9973)
+ b = half*(one + float(ix)/r9973)
+ xplus = (b - x(j))
+ xminus = (-b - x(j))
+ splus = dabs(xplus)
+ sminus = dabs(xminus)
+ jm1 = j - 1
+ j0 = j*jm1/2
+ jj = j0 + j
+ xplus = xplus/l(jj)
+ xminus = xminus/l(jj)
+ if (jm1 .eq. 0) go to 30
+ do 20 i = 1, jm1
+ ji = j0 + i
+ splus = splus + dabs(x(i) + l(ji)*xplus)
+ sminus = sminus + dabs(x(i) + l(ji)*xminus)
+ 20 continue
+ 30 if (sminus .gt. splus) xplus = xminus
+ x(j) = xplus
+! *** update partial sums ***
+ if (jm1 .gt. 0) call vaxpy(jm1, x, xplus, l(j0+1), x)
+ 50 continue
+!
+! *** normalize x ***
+!
+ 60 t = one/v2norm(p, x)
+ do 70 i = 1, p
+ 70 x(i) = t*x(i)
+!
+! *** solve l*y = x and return lsvmin = 1/twonorm(y) ***
+!
+ do 100 j = 1, p
+ jm1 = j - 1
+ j0 = j*jm1/2
+ jj = j0 + j
+ t = zero
+ if (jm1 .gt. 0) t = dotprd(jm1, l(j0+1), y)
+ y(j) = (x(j) - t) / l(jj)
+ 100 continue
+!
+ lsvmin = one/v2norm(p, y)
+ go to 999
+!
+ 110 lsvmin = zero
+ 999 return
+! *** last card of lsvmin follows ***
+ end function lsvmin
+!-----------------------------------------------------------------------------
+ subroutine slvmul(p, y, s, x)
+!
+! *** set y = s * x, s = p x p symmetric matrix. ***
+! *** lower triangle of s stored rowwise. ***
+!
+! *** parameter declarations ***
+!
+ integer :: p
+!al real(kind=8) :: s(1), x(p), y(p)
+ real(kind=8) :: s(p*(p+1)/2), x(p), y(p)
+! dimension s(p*(p+1)/2)
+!
+! *** local variables ***
+!
+ integer :: i, im1, j, k
+ real(kind=8) :: xi
+!
+! *** no intrinsic functions ***
+!
+! *** external function ***
+!
+!el external dotprd
+!el real(kind=8) :: dotprd
+!
+!-----------------------------------------------------------------------
+!
+ j = 1
+ do 10 i = 1, p
+ y(i) = dotprd(i, s(j), x)
+ j = j + i
+ 10 continue
+!
+ if (p .le. 1) go to 999
+ j = 1
+ do 40 i = 2, p
+ xi = x(i)
+ im1 = i - 1
+ j = j + 1
+ do 30 k = 1, im1
+ y(k) = y(k) + s(j)*xi
+ j = j + 1
+ 30 continue
+ 40 continue
+!
+ 999 return
+! *** last card of slvmul follows ***
+ end subroutine slvmul
+!-----------------------------------------------------------------------------
+! minimize_p.F
+!-----------------------------------------------------------------------------
+ subroutine minimize(etot,x,iretcode,nfun)
+
+ use energy, only: func,gradient,fdum!,etotal,enerprint
+ use comm_srutu
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+ integer,parameter :: liv=60
+! integer :: lv=(77+(6*nres)*(6*nres+17)/2) !(77+maxvar*(maxvar+17)/2)) (maxvar=6*maxres)
+!********************************************************************
+! OPTIMIZE sets up SUMSL or DFP and provides a simple interface for *
+! the calling subprogram. *
+! when d(i)=1.0, then v(35) is the length of the initial step, *
+! calculated in the usual pythagorean way. *
+! absolute convergence occurs when the function is within v(31) of *
+! zero. unless you know the minimum value in advance, abs convg *
+! is probably not useful. *
+! relative convergence is when the model predicts that the function *
+! will decrease by less than v(32)*abs(fun). *
+!********************************************************************
+! include 'COMMON.IOUNITS'
+! include 'COMMON.VAR'
+! include 'COMMON.GEO'
+! include 'COMMON.MINIM'
+ integer :: i
+!el common /srutu/ icall
+ integer,dimension(liv) :: iv
+ real(kind=8) :: minval !,v(1:77+(6*nres)*(6*nres+17)/2) !(1:lv)
+!el real(kind=8),dimension(6*nres) :: x,d,xx !(maxvar) (maxvar=6*maxres)
+ real(kind=8),dimension(6*nres) :: x,d,xx !(maxvar) (maxvar=6*maxres)
+ real(kind=8) :: energia(0:n_ene)
+! external func,gradient,fdum
+! external func_restr,grad_restr
+ logical :: not_done,change,reduce
+!el common /przechowalnia/ v
+!el local variables
+ integer :: iretcode,nfun,lv,nvar_restr,idum(1),j
+ real(kind=8) :: etot,rdum(1) !,fdum
+
+ lv=(77+(6*nres)*(6*nres+17)/2) !(77+maxvar*(maxvar+17)/2)) (maxvar=6*maxres)
+
+ if (.not.allocated(v)) allocate(v(1:lv))
+
+ icall = 1
+
+ NOT_DONE=.TRUE.
+
+! DO WHILE (NOT_DONE)
+
+ call deflt(2,iv,liv,lv,v)
+! 12 means fresh start, dont call deflt
+ iv(1)=12
+! max num of fun calls
+ if (maxfun.eq.0) maxfun=500
+ iv(17)=maxfun
+! max num of iterations
+ if (maxmin.eq.0) maxmin=1000
+ iv(18)=maxmin
+! controls output
+ iv(19)=2
+! selects output unit
+ iv(21)=0
+ if (print_min_ini+print_min_stat+print_min_res.gt.0) iv(21)=iout
+! 1 means to print out result
+ iv(22)=print_min_res
+! 1 means to print out summary stats
+ iv(23)=print_min_stat
+! 1 means to print initial x and d
+ iv(24)=print_min_ini
+! min val for v(radfac) default is 0.1
+ v(24)=0.1D0
+! max val for v(radfac) default is 4.0
+ v(25)=2.0D0
+! v(25)=4.0D0
+! check false conv if (act fnctn decrease) .lt. v(26)*(exp decrease)
+! the sumsl default is 0.1
+ v(26)=0.1D0
+! false conv if (act fnctn decrease) .lt. v(34)
+! the sumsl default is 100*machep
+ v(34)=v(34)/100.0D0
+! absolute convergence
+ if (tolf.eq.0.0D0) tolf=1.0D-4
+ v(31)=tolf
+! relative convergence
+ if (rtolf.eq.0.0D0) rtolf=1.0D-4
+ v(32)=rtolf
+! controls initial step size
+ v(35)=1.0D-1
+! large vals of d correspond to small components of step
+ do i=1,nphi
+ d(i)=1.0D-1
+ enddo
+ do i=nphi+1,nvar
+ d(i)=1.0D-1
+ enddo
+!d print *,'Calling SUMSL'
+! call var_to_geom(nvar,x)
+! call chainbuild
+! call etotal(energia(0))
+! etot = energia(0)
+!elmask_r=.true.
+ IF (mask_r) THEN
+ call x2xx(x,xx,nvar_restr)
+ call sumsl(nvar_restr,d,xx,func_restr,grad_restr,&
+ iv,liv,lv,v,idum,rdum,fdum)
+ call xx2x(x,xx)
+ ELSE
+ call sumsl(nvar,d,x,func,gradient,iv,liv,lv,v,idum,rdum,fdum)
+ ENDIF
+ etot=v(10)
+ iretcode=iv(1)
+!d print *,'Exit SUMSL; return code:',iretcode,' energy:',etot
+!d write (iout,'(/a,i4/)') 'SUMSL return code:',iv(1)
+! call intout
+! change=reduce(x)
+ call var_to_geom(nvar,x)
+! if (change) then
+! write (iout,'(a)') 'Reduction worked, minimizing again...'
+! else
+! not_done=.false.
+! endif
+ call chainbuild
+
+!el---------------------
+! write (iout,'(/a)') &
+! "Cartesian coordinates of the reference structure after SUMSL"
+! write (iout,'(a,3(3x,a5),5x,3(3x,a5))') &
+! "Residue","X(CA)","Y(CA)","Z(CA)","X(SC)","Y(SC)","Z(SC)"
+! do i=1,nres
+! write (iout,'(a3,1x,i3,3f8.3,5x,3f8.3)') &
+! restyp(itype(i)),i,(c(j,i),j=1,3),&
+! (c(j,i+nres),j=1,3)
+! enddo
+!el----------------------------
+! call etotal(energia) !sp
+! etot=energia(0)
+! call enerprint(energia) !sp
+ nfun=iv(6)
+
+! write (*,*) 'Processor',MyID,' leaves MINIMIZE.'
+
+! ENDDO ! NOT_DONE
+
+ return
+ end subroutine minimize
+!-----------------------------------------------------------------------------
+! gradient_p.F
+!-----------------------------------------------------------------------------
+ subroutine grad_restr(n,x,nf,g,uiparm,urparm,ufparm)
+
+ use energy, only: cartder,zerograd,etotal,sum_gradient
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+! include 'COMMON.CHAIN'
+! include 'COMMON.DERIV'
+! include 'COMMON.VAR'
+! include 'COMMON.INTERACT'
+! include 'COMMON.FFIELD'
+! include 'COMMON.IOUNITS'
+!EL external ufparm
+ integer :: uiparm(1)
+ real(kind=8) :: urparm(1)
+ real(kind=8),dimension(6*nres) :: x,g !(maxvar) (maxvar=6*maxres)
+ integer :: n,nf,ig,ind,i,j,ij,k,igall
+ real(kind=8) :: f,gphii,gthetai,galphai,gomegai
+ real(kind=8),external :: ufparm
+
+ icg=mod(nf,2)+1
+ if (nf-nfl+1) 20,30,40
+ 20 call func_restr(n,x,nf,f,uiparm,urparm,ufparm)
+! write (iout,*) 'grad 20'
+ if (nf.eq.0) return
+ goto 40
+ 30 continue
+#ifdef OSF
+! Intercept NaNs in the coordinates
+! write(iout,*) (var(i),i=1,nvar)
+ x_sum=0.D0
+ do i=1,n
+ x_sum=x_sum+x(i)
+ enddo
+ if (x_sum.ne.x_sum) then
+ write(iout,*)" *** grad_restr : Found NaN in coordinates"
+ call flush(iout)
+ print *," *** grad_restr : Found NaN in coordinates"
+ return
+ endif
+#endif
+ call var_to_geom_restr(n,x)
+ call chainbuild
+!
+! Evaluate the derivatives of virtual bond lengths and SC vectors in variables.
+!
+ 40 call cartder
+!
+! Convert the Cartesian gradient into internal-coordinate gradient.
+!
+
+ ig=0
+ ind=nres-2
+ do i=2,nres-2
+ IF (mask_phi(i+2).eq.1) THEN
+ gphii=0.0D0
+ do j=i+1,nres-1
+ ind=ind+1
+ do k=1,3
+ gphii=gphii+dcdv(k+3,ind)*gradc(k,j,icg)
+ gphii=gphii+dxdv(k+3,ind)*gradx(k,j,icg)
+ enddo
+ enddo
+ ig=ig+1
+ g(ig)=gphii
+ ELSE
+ ind=ind+nres-1-i
+ ENDIF
+ enddo
+
+
+ ind=0
+ do i=1,nres-2
+ IF (mask_theta(i+2).eq.1) THEN
+ ig=ig+1
+ gthetai=0.0D0
+ do j=i+1,nres-1
+ ind=ind+1
+ do k=1,3
+ gthetai=gthetai+dcdv(k,ind)*gradc(k,j,icg)
+ gthetai=gthetai+dxdv(k,ind)*gradx(k,j,icg)
+ enddo
+ enddo
+ g(ig)=gthetai
+ ELSE
+ ind=ind+nres-1-i
+ ENDIF
+ enddo
+
+ do i=2,nres-1
+ if (itype(i).ne.10) then
+ IF (mask_side(i).eq.1) THEN
+ ig=ig+1
+ galphai=0.0D0
+ do k=1,3
+ galphai=galphai+dxds(k,i)*gradx(k,i,icg)
+ enddo
+ g(ig)=galphai
+ ENDIF
+ endif
+ enddo
+
+
+ do i=2,nres-1
+ if (itype(i).ne.10) then
+ IF (mask_side(i).eq.1) THEN
+ ig=ig+1
+ gomegai=0.0D0
+ do k=1,3
+ gomegai=gomegai+dxds(k+3,i)*gradx(k,i,icg)
+ enddo
+ g(ig)=gomegai
+ ENDIF
+ endif
+ enddo
+
+!
+! Add the components corresponding to local energy terms.
+!
+
+ ig=0
+ igall=0
+ do i=4,nres
+ igall=igall+1
+ if (mask_phi(i).eq.1) then
+ ig=ig+1
+ g(ig)=g(ig)+gloc(igall,icg)
+ endif
+ enddo
+
+ do i=3,nres
+ igall=igall+1
+ if (mask_theta(i).eq.1) then
+ ig=ig+1
+ g(ig)=g(ig)+gloc(igall,icg)
+ endif
+ enddo
+
+ do ij=1,2
+ do i=2,nres-1
+ if (itype(i).ne.10) then
+ igall=igall+1
+ if (mask_side(i).eq.1) then
+ ig=ig+1
+ g(ig)=g(ig)+gloc(igall,icg)
+ endif
+ endif
+ enddo
+ enddo
+
+!d do i=1,ig
+!d write (iout,'(a2,i5,a3,f25.8)') 'i=',i,' g=',g(i)
+!d enddo
+ return
+ end subroutine grad_restr
+!-----------------------------------------------------------------------------
+ subroutine func_restr(n,x,nf,f,uiparm,urparm,ufparm) !from minimize_p.F
+
+ use comm_chu
+ use energy, only: zerograd,etotal,sum_gradient
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+! include 'COMMON.DERIV'
+! include 'COMMON.IOUNITS'
+! include 'COMMON.GEO'
+ integer :: n,nf
+!el integer :: jjj
+!el common /chuju/ jjj
+ real(kind=8) :: energia(0:n_ene)
+ real(kind=8) :: f
+ real(kind=8),external :: ufparm
+ integer :: uiparm(1)
+ real(kind=8) :: urparm(1)
+ real(kind=8),dimension(6*nres) :: x !(maxvar) (maxvar=6*maxres)
+! if (jjj.gt.0) then
+! write (iout,'(10f8.3)') (rad2deg*x(i),i=1,n)
+! endif
+ nfl=nf
+ icg=mod(nf,2)+1
+ call var_to_geom_restr(n,x)
+ call zerograd
+ call chainbuild
+!d write (iout,*) 'ETOTAL called from FUNC'
+ call etotal(energia)
+ call sum_gradient
+ f=energia(0)
+! if (jjj.gt.0) then
+! write (iout,'(10f8.3)') (rad2deg*x(i),i=1,n)
+! write (iout,*) 'f=',etot
+! jjj=0
+! endif
+ return
+ end subroutine func_restr
+!-----------------------------------------------------------------------------
+! subroutine func(n,x,nf,f,uiparm,urparm,ufparm) in module energy
+!-----------------------------------------------------------------------------
+ subroutine x2xx(x,xx,n)
+
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+! include 'COMMON.VAR'
+! include 'COMMON.CHAIN'
+! include 'COMMON.INTERACT'
+ integer :: n,i,ij,ig,igall
+ real(kind=8),dimension(6*nres) :: xx,x !(maxvar) (maxvar=6*maxres)
+
+!el allocate(varall(nvar)) allocated in alioc_ener_arrays
+
+ do i=1,nvar
+ varall(i)=x(i)
+ enddo
+
+ ig=0
+ igall=0
+ do i=4,nres
+ igall=igall+1
+ if (mask_phi(i).eq.1) then
+ ig=ig+1
+ xx(ig)=x(igall)
+ endif
+ enddo
+
+ do i=3,nres
+ igall=igall+1
+ if (mask_theta(i).eq.1) then
+ ig=ig+1
+ xx(ig)=x(igall)
+ endif
+ enddo
+
+ do ij=1,2
+ do i=2,nres-1
+ if (itype(i).ne.10) then
+ igall=igall+1
+ if (mask_side(i).eq.1) then
+ ig=ig+1
+ xx(ig)=x(igall)
+ endif
+ endif
+ enddo
+ enddo
+
+ n=ig
+
+ return
+ end subroutine x2xx
+!-----------------------------------------------------------------------------
+!el subroutine xx2x(x,xx) in module math
+!-----------------------------------------------------------------------------
+ subroutine minim_dc(etot,iretcode,nfun)
+
+ use MPI_data
+ use energy, only: fdum,check_ecartint
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+#ifdef MPI
+ include 'mpif.h'
+#endif
+ integer,parameter :: liv=60
+! integer :: lv=(77+(6*nres)*(6*nres+17)/2) !(77+maxvar*(maxvar+17)/2)) (maxvar=6*maxres)
+! include 'COMMON.SETUP'
+! include 'COMMON.IOUNITS'
+! include 'COMMON.VAR'
+! include 'COMMON.GEO'
+! include 'COMMON.MINIM'
+! include 'COMMON.CHAIN'
+ integer :: iretcode,nfun,k,i,j,lv,idum(1)
+ integer,dimension(liv) :: iv
+ real(kind=8) :: minval !,v(1:77+(6*nres)*(6*nres+17)/2) !(1:lv)
+ real(kind=8),dimension(6*nres) :: x,d,xx !(maxvar) (maxvar=6*maxres)
+!el common /przechowalnia/ v
+
+ real(kind=8) :: energia(0:n_ene)
+! external func_dc,grad_dc ,fdum
+ logical :: not_done,change,reduce
+ real(kind=8) :: g(6*nres),f1,etot,rdum(1) !,fdum
+
+ lv=(77+(6*nres)*(6*nres+17)/2) !(77+maxvar*(maxvar+17)/2)) (maxvar=6*maxres)
+
+ if (.not. allocated(v)) allocate(v(1:lv))
+
+ call deflt(2,iv,liv,lv,v)
+! 12 means fresh start, dont call deflt
+ iv(1)=12
+! max num of fun calls
+ if (maxfun.eq.0) maxfun=500
+ iv(17)=maxfun
+! max num of iterations
+ if (maxmin.eq.0) maxmin=1000
+ iv(18)=maxmin
+! controls output
+ iv(19)=2
+! selects output unit
+ iv(21)=0
+ if (print_min_ini+print_min_stat+print_min_res.gt.0) iv(21)=iout
+! 1 means to print out result
+ iv(22)=print_min_res
+! 1 means to print out summary stats
+ iv(23)=print_min_stat
+! 1 means to print initial x and d
+ iv(24)=print_min_ini
+! min val for v(radfac) default is 0.1
+ v(24)=0.1D0
+! max val for v(radfac) default is 4.0
+ v(25)=2.0D0
+! v(25)=4.0D0
+! check false conv if (act fnctn decrease) .lt. v(26)*(exp decrease)
+! the sumsl default is 0.1
+ v(26)=0.1D0
+! false conv if (act fnctn decrease) .lt. v(34)
+! the sumsl default is 100*machep
+ v(34)=v(34)/100.0D0
+! absolute convergence
+ if (tolf.eq.0.0D0) tolf=1.0D-4
+ v(31)=tolf
+! relative convergence
+ if (rtolf.eq.0.0D0) rtolf=1.0D-4
+ v(32)=rtolf
+! controls initial step size
+ v(35)=1.0D-1
+! large vals of d correspond to small components of step
+ do i=1,6*nres
+ d(i)=1.0D-1
+ enddo
+
+ k=0
+ do i=1,nres-1
+ do j=1,3
+ k=k+1
+ x(k)=dc(j,i)
+ enddo
+ enddo
+ do i=2,nres-1
+ if (ialph(i,1).gt.0) then
+ do j=1,3
+ k=k+1
+ x(k)=dc(j,i+nres)
+ enddo
+ endif
+ enddo
+ call check_ecartint
+ call sumsl(k,d,x,func_dc,grad_dc,iv,liv,lv,v,idum,rdum,fdum)
+ call check_ecartint
+ k=0
+ do i=1,nres-1
+ do j=1,3
+ k=k+1
+ dc(j,i)=x(k)
+ enddo
+ enddo
+ do i=2,nres-1
+ if (ialph(i,1).gt.0) then
+ do j=1,3
+ k=k+1
+ dc(j,i+nres)=x(k)
+ enddo
+ endif
+ enddo
+ call chainbuild_cart
+
+!d call zerograd
+!d nf=0
+!d call func_dc(k,x,nf,f,idum,rdum,fdum)
+!d call grad_dc(k,x,nf,g,idum,rdum,fdum)
+!d
+!d do i=1,k
+!d x(i)=x(i)+1.0D-5
+!d call func_dc(k,x,nf,f1,idum,rdum,fdum)
+!d x(i)=x(i)-1.0D-5
+!d print '(i5,2f15.5)',i,g(i),(f1-f)/1.0D-5
+!d enddo
+!el---------------------
+! write (iout,'(/a)') &
+! "Cartesian coordinates of the reference structure after SUMSL"
+! write (iout,'(a,3(3x,a5),5x,3(3x,a5))') &
+! "Residue","X(CA)","Y(CA)","Z(CA)","X(SC)","Y(SC)","Z(SC)"
+! do i=1,nres
+! write (iout,'(a3,1x,i3,3f8.3,5x,3f8.3)') &
+! restyp(itype(i)),i,(c(j,i),j=1,3),&
+! (c(j,i+nres),j=1,3)
+! enddo
+!el----------------------------
+ etot=v(10)
+ iretcode=iv(1)
+ nfun=iv(6)
+ return
+ end subroutine minim_dc
+!-----------------------------------------------------------------------------
+ subroutine func_dc(n,x,nf,f,uiparm,urparm,ufparm)
+
+ use MPI_data
+ use energy, only: zerograd,etotal
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+#ifdef MPI
+ include 'mpif.h'
+#endif
+! include 'COMMON.SETUP'
+! include 'COMMON.DERIV'
+! include 'COMMON.IOUNITS'
+! include 'COMMON.GEO'
+! include 'COMMON.CHAIN'
+! include 'COMMON.VAR'
+ integer :: n,nf,k,i,j
+ real(kind=8) :: energia(0:n_ene)
+ real(kind=8),external :: ufparm
+ integer :: uiparm(1)
+ real(kind=8) :: urparm(1)
+ real(kind=8),dimension(6*nres) :: x !(maxvar) (maxvar=6*maxres)
+ real(kind=8) :: f
+ nfl=nf
+!bad icg=mod(nf,2)+1
+ icg=1
+
+ k=0
+ do i=1,nres-1
+ do j=1,3
+ k=k+1
+ dc(j,i)=x(k)
+ enddo
+ enddo
+ do i=2,nres-1
+ if (ialph(i,1).gt.0) then
+ do j=1,3
+ k=k+1
+ dc(j,i+nres)=x(k)
+ enddo
+ endif
+ enddo
+ call chainbuild_cart
+
+ call zerograd
+ call etotal(energia)
+ f=energia(0)
+
+!d print *,'func_dc ',nf,nfl,f
+
+ return
+ end subroutine func_dc
+!-----------------------------------------------------------------------------
+ subroutine grad_dc(n,x,nf,g,uiparm,urparm,ufparm)
+
+ use MPI_data
+ use energy, only: cartgrad,zerograd,etotal
+! use MD_data
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+#ifdef MPI
+ include 'mpif.h'
+#endif
+! include 'COMMON.SETUP'
+! include 'COMMON.CHAIN'
+! include 'COMMON.DERIV'
+! include 'COMMON.VAR'
+! include 'COMMON.INTERACT'
+! include 'COMMON.FFIELD'
+! include 'COMMON.MD'
+! include 'COMMON.IOUNITS'
+ real(kind=8),external :: ufparm
+ integer :: n,nf,i,j,k
+ integer :: uiparm(1)
+ real(kind=8) :: urparm(1)
+ real(kind=8),dimension(6*nres) :: x,g !(maxvar) (maxvar=6*maxres)
+ real(kind=8) :: f
+!
+!elwrite(iout,*) "jestesmy w grad dc"
+!
+!bad icg=mod(nf,2)+1
+ icg=1
+!d print *,'grad_dc ',nf,nfl,nf-nfl+1,icg
+!elwrite(iout,*) "jestesmy w grad dc nf-nfl+1", nf-nfl+1
+ if (nf-nfl+1) 20,30,40
+ 20 call func_dc(n,x,nf,f,uiparm,urparm,ufparm)
+!d print *,20
+ if (nf.eq.0) return
+ goto 40
+ 30 continue
+!d print *,30
+ k=0
+ do i=1,nres-1
+ do j=1,3
+ k=k+1
+ dc(j,i)=x(k)
+ enddo
+ enddo
+ do i=2,nres-1
+ if (ialph(i,1).gt.0) then
+ do j=1,3
+ k=k+1
+ dc(j,i+nres)=x(k)
+ enddo
+ endif
+ enddo
+!elwrite(iout,*) "jestesmy w grad dc"
+ call chainbuild_cart
+
+!
+! Evaluate the derivatives of virtual bond lengths and SC vectors in variables.
+!
+ 40 call cartgrad
+!d print *,40
+!elwrite(iout,*) "jestesmy w grad dc"
+ k=0
+ do i=1,nres-1
+ do j=1,3
+ k=k+1
+ g(k)=gcart(j,i)
+ enddo
+ enddo
+ do i=2,nres-1
+ if (ialph(i,1).gt.0) then
+ do j=1,3
+ k=k+1
+ g(k)=gxcart(j,i)
+ enddo
+ endif
+ enddo
+!elwrite(iout,*) "jestesmy w grad dc"
+
+ return
+ end subroutine grad_dc
+!-----------------------------------------------------------------------------
+! minim_mcmf.F
+!-----------------------------------------------------------------------------
+#ifdef MPI
+ subroutine minim_mcmf
+
+ use MPI_data
+ use csa_data
+ use energy, only: func,gradient,fdum
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+ include 'mpif.h'
+ integer,parameter :: liv=60
+! integer :: lv=(77+(6*nres)*(6*nres+17)/2) !(77+maxvar*(maxvar+17)/2)) (maxvar=6*maxres)
+! include 'COMMON.VAR'
+! include 'COMMON.IOUNITS'
+! include 'COMMON.MINIM'
+! real(kind=8) :: fdum
+! external func,gradient,fdum
+!el real(kind=4) :: ran1,ran2,ran3
+! include 'COMMON.SETUP'
+! include 'COMMON.GEO'
+! include 'COMMON.CHAIN'
+! include 'COMMON.FFIELD'
+ real(kind=8),dimension(6*nres) :: var !(maxvar) (maxvar=6*maxres)
+ real(kind=8),dimension(mxch*(mxch+1)/2+1) :: erg
+ real(kind=8),dimension(6*nres) :: d,garbage !(maxvar) (maxvar=6*maxres)
+!el real(kind=8) :: v(1:77+(6*nres)*(6*nres+17)/2+1)
+ integer,dimension(6) :: indx
+ integer,dimension(liv) :: iv
+ integer :: lv,idum(1),nf !
+ real(kind=8) :: rdum(1)
+ real(kind=8) :: przes(3),obrot(3,3),eee
+ logical :: non_conv
+
+ integer,dimension(MPI_STATUS_SIZE) :: muster
+
+ integer :: ichuj,i,ierr
+ real(kind=8) :: rad,ene0
+ data rad /1.745329252d-2/
+!el common /przechowalnia/ v
+
+ lv=(77+(6*nres)*(6*nres+17)/2) !(77+maxvar*(maxvar+17)/2)) (maxvar=6*maxres)
+ if (.not. allocated(v)) allocate(v(1:lv))
+
+ ichuj=0
+ 10 continue
+ ichuj = ichuj + 1
+ call mpi_recv(indx,6,mpi_integer,king,idint,CG_COMM,&
+ muster,ierr)
+ if (indx(1).eq.0) return
+! print *, 'worker ',me,' received order ',n,ichuj
+ call mpi_recv(var,nvar,mpi_double_precision,&
+ king,idreal,CG_COMM,muster,ierr)
+ call mpi_recv(ene0,1,mpi_double_precision,&
+ king,idreal,CG_COMM,muster,ierr)
+! print *, 'worker ',me,' var read '
+
+
+ call deflt(2,iv,liv,lv,v)
+! 12 means fresh start, dont call deflt
+ iv(1)=12
+! max num of fun calls
+ if (maxfun.eq.0) maxfun=500
+ iv(17)=maxfun
+! max num of iterations
+ if (maxmin.eq.0) maxmin=1000
+ iv(18)=maxmin
+! controls output
+ iv(19)=2
+! selects output unit
+! iv(21)=iout
+ iv(21)=0
+! 1 means to print out result
+ iv(22)=0
+! 1 means to print out summary stats
+ iv(23)=0
+! 1 means to print initial x and d
+ iv(24)=0
+! min val for v(radfac) default is 0.1
+ v(24)=0.1D0
+! max val for v(radfac) default is 4.0
+ v(25)=2.0D0
+! check false conv if (act fnctn decrease) .lt. v(26)*(exp decrease)
+! the sumsl default is 0.1
+ v(26)=0.1D0
+! false conv if (act fnctn decrease) .lt. v(34)
+! the sumsl default is 100*machep
+ v(34)=v(34)/100.0D0
+! absolute convergence
+ if (tolf.eq.0.0D0) tolf=1.0D-4
+ v(31)=tolf
+! relative convergence
+ if (rtolf.eq.0.0D0) rtolf=1.0D-4
+ v(32)=rtolf
+! controls initial step size
+ v(35)=1.0D-1
+! large vals of d correspond to small components of step
+ do i=1,nphi
+ d(i)=1.0D-1
+ enddo
+ do i=nphi+1,nvar
+ d(i)=1.0D-1
+ enddo
+! minimize energy
+
+ call func(nvar,var,nf,eee,idum,rdum,fdum)
+ if(eee.gt.1.0d18) then
+! print *,'MINIM_JLEE: ',me,' CHUJ NASTAPIL'
+! print *,' energy before SUMSL =',eee
+! print *,' aborting local minimization'
+ iv(1)=-1
+ v(10)=eee
+ nf=1
+ go to 201
+ endif
+
+ call sumsl(nvar,d,var,func,gradient,iv,liv,lv,v,idum,rdum,fdum)
+! find which conformation was returned from sumsl
+ nf=iv(7)+1
+ 201 continue
+! total # of ftn evaluations (for iwf=0, it includes all minimizations).
+ indx(4)=nf
+ indx(5)=iv(1)
+ eee=v(10)
+
+ call mpi_send(indx,6,mpi_integer,king,idint,CG_COMM,&
+ ierr)
+! print '(a5,i3,15f10.5)', 'ENEX0',indx(1),v(10)
+ call mpi_send(var,nvar,mpi_double_precision,&
+ king,idreal,CG_COMM,ierr)
+ call mpi_send(eee,1,mpi_double_precision,king,idreal,&
+ CG_COMM,ierr)
+ call mpi_send(ene0,1,mpi_double_precision,king,idreal,&
+ CG_COMM,ierr)
+ go to 10
+ return
+ end subroutine minim_mcmf
+#endif
+!-----------------------------------------------------------------------------
+! rmdd.f
+!-----------------------------------------------------------------------------
+! algorithm 611, collected algorithms from acm.
+! algorithm appeared in acm-trans. math. software, vol.9, no. 4,
+! dec., 1983, p. 503-524.
+ integer function imdcon(k)
+!
+ integer :: k
+!
+! *** return integer machine-dependent constants ***
+!
+! *** k = 1 means return standard output unit number. ***
+! *** k = 2 means return alternate output unit number. ***
+! *** k = 3 means return input unit number. ***
+! (note -- k = 2, 3 are used only by test programs.)
+!
+! +++ port version follows...
+! external i1mach
+! integer i1mach
+! integer mdperm(3)
+! data mdperm(1)/2/, mdperm(2)/4/, mdperm(3)/1/
+! imdcon = i1mach(mdperm(k))
+! +++ end of port version +++
+!
+! +++ non-port version follows...
+ integer :: mdcon(3)
+ data mdcon(1)/6/, mdcon(2)/8/, mdcon(3)/5/
+ imdcon = mdcon(k)
+! +++ end of non-port version +++
+!
+ 999 return
+! *** last card of imdcon follows ***
+ end function imdcon
+!-----------------------------------------------------------------------------
+ real(kind=8) function rmdcon(k)
+!
+! *** return machine dependent constants used by nl2sol ***
+!
+! +++ comments below contain data statements for various machines. +++
+! +++ to convert to another machine, place a c in column 1 of the +++
+! +++ data statement line(s) that correspond to the current machine +++
+! +++ and remove the c from column 1 of the data statement line(s) +++
+! +++ that correspond to the new machine. +++
+!
+ integer :: k
+!
+! *** the constant returned depends on k...
+!
+! *** k = 1... smallest pos. eta such that -eta exists.
+! *** k = 2... square root of eta.
+! *** k = 3... unit roundoff = smallest pos. no. machep such
+! *** that 1 + machep .gt. 1 .and. 1 - machep .lt. 1.
+! *** k = 4... square root of machep.
+! *** k = 5... square root of big (see k = 6).
+! *** k = 6... largest machine no. big such that -big exists.
+!
+ real(kind=8) :: big, eta, machep
+ integer :: bigi(4), etai(4), machei(4)
+!/+
+!el real(kind=8) :: dsqrt
+!/
+ equivalence (big,bigi(1)), (eta,etai(1)), (machep,machei(1))
+!
+! +++ ibm 360, ibm 370, or xerox +++
+!
+! data big/z7fffffffffffffff/, eta/z0010000000000000/,
+! 1 machep/z3410000000000000/
+!
+! +++ data general +++
+!
+! data big/0.7237005577d+76/, eta/0.5397605347d-78/,
+! 1 machep/2.22044605d-16/
+!
+! +++ dec 11 +++
+!
+! data big/1.7d+38/, eta/2.938735878d-39/, machep/2.775557562d-17/
+!
+! +++ hp3000 +++
+!
+! data big/1.157920892d+77/, eta/8.636168556d-78/,
+! 1 machep/5.551115124d-17/
+!
+! +++ honeywell +++
+!
+! data big/1.69d+38/, eta/5.9d-39/, machep/2.1680435d-19/
+!
+! +++ dec10 +++
+!
+! data big/"377777100000000000000000/,
+! 1 eta/"002400400000000000000000/,
+! 2 machep/"104400000000000000000000/
+!
+! +++ burroughs +++
+!
+! data big/o0777777777777777,o7777777777777777/,
+! 1 eta/o1771000000000000,o7770000000000000/,
+! 2 machep/o1451000000000000,o0000000000000000/
+!
+! +++ control data +++
+!
+! data big/37767777777777777777b,37167777777777777777b/,
+! 1 eta/00014000000000000000b,00000000000000000000b/,
+! 2 machep/15614000000000000000b,15010000000000000000b/
+!
+! +++ prime +++
+!
+! data big/1.0d+9786/, eta/1.0d-9860/, machep/1.4210855d-14/
+!
+! +++ univac +++
+!
+! data big/8.988d+307/, eta/1.2d-308/, machep/1.734723476d-18/
+!
+! +++ vax +++
+!
+ data big/1.7d+38/, eta/2.939d-39/, machep/1.3877788d-17/
+!
+! +++ cray 1 +++
+!
+! data bigi(1)/577767777777777777777b/,
+! 1 bigi(2)/000007777777777777776b/,
+! 2 etai(1)/200004000000000000000b/,
+! 3 etai(2)/000000000000000000000b/,
+! 4 machei(1)/377224000000000000000b/,
+! 5 machei(2)/000000000000000000000b/
+!
+! +++ port library -- requires more than just a data statement... +++
+!
+! external d1mach
+! double precision d1mach, zero
+! data big/0.d+0/, eta/0.d+0/, machep/0.d+0/, zero/0.d+0/
+! if (big .gt. zero) go to 1
+! big = d1mach(2)
+! eta = d1mach(1)
+! machep = d1mach(4)
+!1 continue
+!
+! +++ end of port +++
+!
+!------------------------------- body --------------------------------
+!
+ go to (10, 20, 30, 40, 50, 60), k
+!
+ 10 rmdcon = eta
+ go to 999
+!
+ 20 rmdcon = dsqrt(256.d+0*eta)/16.d+0
+ go to 999
+!
+ 30 rmdcon = machep
+ go to 999
+!
+ 40 rmdcon = dsqrt(machep)
+ go to 999
+!
+ 50 rmdcon = dsqrt(big/256.d+0)*16.d+0
+ go to 999
+!
+ 60 rmdcon = big
+!
+ 999 return
+! *** last card of rmdcon follows ***
+ end function rmdcon
+!-----------------------------------------------------------------------------
+! sc_move.F
+!-----------------------------------------------------------------------------
+ subroutine sc_move(n_start,n_end,n_maxtry,e_drop,n_fun,etot)
+
+ use control
+ use random, only: iran_num
+ use energy, only: esc
+! Perform a quick search over side-chain arrangments (over
+! residues n_start to n_end) for a given (frozen) CA trace
+! Only side-chains are minimized (at most n_maxtry times each),
+! not CA positions
+! Stops if energy drops by e_drop, otherwise tries all residues
+! in the given range
+! If there is an energy drop, full minimization may be useful
+! n_start, n_end CAN be modified by this routine, but only if
+! out of bounds (n_start <= 1, n_end >= nres, n_start < n_end)
+! NOTE: this move should never increase the energy
+!rc implicit none
+
+! Includes
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+ include 'mpif.h'
+! include 'COMMON.GEO'
+! include 'COMMON.VAR'
+! include 'COMMON.HEADER'
+! include 'COMMON.IOUNITS'
+! include 'COMMON.CHAIN'
+! include 'COMMON.FFIELD'
+
+! External functions
+!el integer iran_num
+!el external iran_num
+
+! Input arguments
+ integer :: n_start,n_end,n_maxtry
+ real(kind=8) :: e_drop
+
+! Output arguments
+ integer :: n_fun
+ real(kind=8) :: etot
+
+! Local variables
+! real(kind=8) :: energy(0:n_ene)
+ real(kind=8) :: cur_alph(2:nres-1),cur_omeg(2:nres-1)
+ real(kind=8) :: orig_e,cur_e
+ integer :: n,n_steps,n_first,n_cur,n_tot !,i
+ real(kind=8) :: orig_w(0:n_ene)
+ real(kind=8) :: wtime
+
+!elwrite(iout,*) "in sc_move etot= ", etot
+! Set non side-chain weights to zero (minimization is faster)
+! NOTE: e(2) does not actually depend on the side-chain, only CA
+ orig_w(2)=wscp
+ orig_w(3)=welec
+ orig_w(4)=wcorr
+ orig_w(5)=wcorr5
+ orig_w(6)=wcorr6
+ orig_w(7)=wel_loc
+ orig_w(8)=wturn3
+ orig_w(9)=wturn4
+ orig_w(10)=wturn6
+ orig_w(11)=wang
+ orig_w(13)=wtor
+ orig_w(14)=wtor_d
+ orig_w(15)=wvdwpp
+
+ wscp=0.D0
+ welec=0.D0
+ wcorr=0.D0
+ wcorr5=0.D0
+ wcorr6=0.D0
+ wel_loc=0.D0
+ wturn3=0.D0
+ wturn4=0.D0
+ wturn6=0.D0
+ wang=0.D0
+ wtor=0.D0
+ wtor_d=0.D0
+ wvdwpp=0.D0
+
+! Make sure n_start, n_end are within proper range
+ if (n_start.lt.2) n_start=2
+ if (n_end.gt.nres-1) n_end=nres-1
+!rc if (n_start.lt.n_end) then
+ if (n_start.gt.n_end) then
+ n_start=2
+ n_end=nres-1
+ endif
+
+! Save the initial values of energy and coordinates
+!d call chainbuild
+!d call etotal(energy)
+!d write (iout,*) 'start sc ene',energy(0)
+!d call enerprint(energy(0))
+!rc etot=energy(0)
+ n_fun=0
+!rc orig_e=etot
+!rc cur_e=orig_e
+!rc do i=2,nres-1
+!rc cur_alph(i)=alph(i)
+!rc cur_omeg(i)=omeg(i)
+!rc enddo
+
+!t wtime=MPI_WTIME()
+! Try (one by one) all specified residues, starting from a
+! random position in sequence
+! Stop early if the energy has decreased by at least e_drop
+ n_tot=n_end-n_start+1
+ n_first=iran_num(0,n_tot-1)
+ n_steps=0
+ n=0
+!rc do while (n.lt.n_tot .and. orig_e-etot.lt.e_drop)
+ do while (n.lt.n_tot)
+ n_cur=n_start+mod(n_first+n,n_tot)
+ call single_sc_move(n_cur,n_maxtry,e_drop,&
+ n_steps,n_fun,etot)
+!elwrite(iout,*) "after msingle sc_move etot= ", etot
+! If a lower energy was found, update the current structure...
+!rc if (etot.lt.cur_e) then
+!rc cur_e=etot
+!rc do i=2,nres-1
+!rc cur_alph(i)=alph(i)
+!rc cur_omeg(i)=omeg(i)
+!rc enddo
+!rc else
+! ...else revert to the previous one
+!rc etot=cur_e
+!rc do i=2,nres-1
+!rc alph(i)=cur_alph(i)
+!rc omeg(i)=cur_omeg(i)
+!rc enddo
+!rc endif
+ n=n+1
+!d
+!d call chainbuild
+!d call etotal(energy)
+!d print *,'running',n,energy(0)
+ enddo
+
+!d call chainbuild
+!d call etotal(energy)
+!d write (iout,*) 'end sc ene',energy(0)
+
+! Put the original weights back to calculate the full energy
+ wscp=orig_w(2)
+ welec=orig_w(3)
+ wcorr=orig_w(4)
+ wcorr5=orig_w(5)
+ wcorr6=orig_w(6)
+ wel_loc=orig_w(7)
+ wturn3=orig_w(8)
+ wturn4=orig_w(9)
+ wturn6=orig_w(10)
+ wang=orig_w(11)
+ wtor=orig_w(13)
+ wtor_d=orig_w(14)
+ wvdwpp=orig_w(15)
+
+!rc n_fun=n_fun+1
+!t write (iout,*) 'sc_local time= ',MPI_WTIME()-wtime
+ return
+ end subroutine sc_move
+!-----------------------------------------------------------------------------
+ subroutine single_sc_move(res_pick,n_maxtry,e_drop,n_steps,n_fun,e_sc)
+
+! Perturb one side-chain (res_pick) and minimize the
+! neighbouring region, keeping all CA's and non-neighbouring
+! side-chains fixed
+! Try until e_drop energy improvement is achieved, or n_maxtry
+! attempts have been made
+! At the start, e_sc should contain the side-chain-only energy(0)
+! nsteps and nfun for this move are ADDED to n_steps and n_fun
+!rc implicit none
+ use energy, only: esc
+ use geometry, only:dist
+! Includes
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+! include 'COMMON.VAR'
+! include 'COMMON.INTERACT'
+! include 'COMMON.CHAIN'
+! include 'COMMON.MINIM'
+! include 'COMMON.FFIELD'
+! include 'COMMON.IOUNITS'
+
+! External functions
+!el double precision dist
+!el external dist
+
+! Input arguments
+ integer :: res_pick,n_maxtry
+ real(kind=8) :: e_drop
+
+! Input/Output arguments
+ integer :: n_steps,n_fun
+ real(kind=8) :: e_sc
+
+! Local variables
+ logical :: fail
+ integer :: i,j
+ integer :: nres_moved
+ integer :: iretcode,loc_nfun,orig_maxfun,n_try
+ real(kind=8) :: sc_dist,sc_dist_cutoff
+! real(kind=8) :: energy_(0:n_ene)
+ real(kind=8) :: evdw,escloc,orig_e,cur_e
+ real(kind=8) :: cur_alph(2:nres-1),cur_omeg(2:nres-1)
+ real(kind=8) :: var(6*nres) !(maxvar) (maxvar=6*maxres)
+
+ real(kind=8) :: orig_theta(1:nres),orig_phi(1:nres),&
+ orig_alph(1:nres),orig_omeg(1:nres)
+
+!elwrite(iout,*) "in sinle etot/ e_sc",e_sc
+! Define what is meant by "neighbouring side-chain"
+ sc_dist_cutoff=5.0D0
+
+! Don't do glycine or ends
+ i=itype(res_pick)
+ if (i.eq.10 .or. i.eq.ntyp1) return
+
+! Freeze everything (later will relax only selected side-chains)
+ mask_r=.true.
+ do i=1,nres
+ mask_phi(i)=0
+ mask_theta(i)=0
+ mask_side(i)=0
+ enddo
+
+! Find the neighbours of the side-chain to move
+! and save initial variables
+!rc orig_e=e_sc
+!rc cur_e=orig_e
+ nres_moved=0
+ do i=2,nres-1
+! Don't do glycine (itype(j)==10)
+ if (itype(i).ne.10) then
+ sc_dist=dist(nres+i,nres+res_pick)
+ else
+ sc_dist=sc_dist_cutoff
+ endif
+ if (sc_dist.lt.sc_dist_cutoff) then
+ nres_moved=nres_moved+1
+ mask_side(i)=1
+ cur_alph(i)=alph(i)
+ cur_omeg(i)=omeg(i)
+ endif
+ enddo
+
+ call chainbuild
+ call egb1(evdw)
+ call esc(escloc)
+!elwrite(iout,*) "in sinle etot/ e_sc",e_sc
+!elwrite(iout,*) "in sinle wsc=",wsc,"evdw",evdw,"wscloc",wscloc,"escloc",escloc
+ e_sc=wsc*evdw+wscloc*escloc
+!elwrite(iout,*) "in sinle etot/ e_sc",e_sc
+!d call etotal(energy)
+!d print *,'new ',(energy(k),k=0,n_ene)
+ orig_e=e_sc
+ cur_e=orig_e
+
+ n_try=0
+ do while (n_try.lt.n_maxtry .and. orig_e-cur_e.lt.e_drop)
+! Move the selected residue (don't worry if it fails)
+ call gen_side(iabs(itype(res_pick)),theta(res_pick+1),&
+ alph(res_pick),omeg(res_pick),fail)
+
+! Minimize the side-chains starting from the new arrangement
+ call geom_to_var(nvar,var)
+ orig_maxfun=maxfun
+ maxfun=7
+
+!rc do i=1,nres
+!rc orig_theta(i)=theta(i)
+!rc orig_phi(i)=phi(i)
+!rc orig_alph(i)=alph(i)
+!rc orig_omeg(i)=omeg(i)
+!rc enddo
+
+!elwrite(iout,*) "in sinle etot/ e_sc",e_sc
+ call minimize_sc1(e_sc,var,iretcode,loc_nfun)
+
+!elwrite(iout,*) "in sinle etot/ e_sc",e_sc
+!v write(*,'(2i3,2f12.5,2i3)')
+!v & res_pick,nres_moved,orig_e,e_sc-cur_e,
+!v & iretcode,loc_nfun
+
+!$$$ if (iretcode.eq.8) then
+!$$$ write(iout,*)'Coordinates just after code 8'
+!$$$ call chainbuild
+!$$$ call all_varout
+!$$$ call flush(iout)
+!$$$ do i=1,nres
+!$$$ theta(i)=orig_theta(i)
+!$$$ phi(i)=orig_phi(i)
+!$$$ alph(i)=orig_alph(i)
+!$$$ omeg(i)=orig_omeg(i)
+!$$$ enddo
+!$$$ write(iout,*)'Coordinates just before code 8'
+!$$$ call chainbuild
+!$$$ call all_varout
+!$$$ call flush(iout)
+!$$$ endif
+
+ n_fun=n_fun+loc_nfun
+ maxfun=orig_maxfun
+ call var_to_geom(nvar,var)
+
+! If a lower energy was found, update the current structure...
+ if (e_sc.lt.cur_e) then
+!v call chainbuild
+!v call etotal(energy)
+!d call egb1(evdw)
+!d call esc(escloc)
+!d e_sc1=wsc*evdw+wscloc*escloc
+!d print *,' new',e_sc1,energy(0)
+!v print *,'new ',energy(0)
+!d call enerprint(energy(0))
+ cur_e=e_sc
+ do i=2,nres-1
+ if (mask_side(i).eq.1) then
+ cur_alph(i)=alph(i)
+ cur_omeg(i)=omeg(i)
+ endif
+ enddo
+ else
+! ...else revert to the previous one
+ e_sc=cur_e
+ do i=2,nres-1
+ if (mask_side(i).eq.1) then
+ alph(i)=cur_alph(i)
+ omeg(i)=cur_omeg(i)
+ endif
+ enddo
+ endif
+ n_try=n_try+1
+
+ enddo
+ n_steps=n_steps+n_try
+
+! Reset the minimization mask_r to false
+ mask_r=.false.
+
+ return
+ end subroutine single_sc_move
+!-----------------------------------------------------------------------------
+ subroutine sc_minimize(etot,iretcode,nfun)
+
+! Minimizes side-chains only, leaving backbone frozen
+!rc implicit none
+ use energy, only: etotal
+! Includes
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+! include 'COMMON.VAR'
+! include 'COMMON.CHAIN'
+! include 'COMMON.FFIELD'
+
+! Output arguments
+ real(kind=8) :: etot
+ integer :: iretcode,nfun
+
+! Local variables
+ integer :: i
+ real(kind=8) :: orig_w(0:n_ene),energy_(0:n_ene)
+ real(kind=8) :: var(6*nres) !(maxvar)(maxvar=6*maxres)
+
+
+! Set non side-chain weights to zero (minimization is faster)
+! NOTE: e(2) does not actually depend on the side-chain, only CA
+ orig_w(2)=wscp
+ orig_w(3)=welec
+ orig_w(4)=wcorr
+ orig_w(5)=wcorr5
+ orig_w(6)=wcorr6
+ orig_w(7)=wel_loc
+ orig_w(8)=wturn3
+ orig_w(9)=wturn4
+ orig_w(10)=wturn6
+ orig_w(11)=wang
+ orig_w(13)=wtor
+ orig_w(14)=wtor_d
+
+ wscp=0.D0
+ welec=0.D0
+ wcorr=0.D0
+ wcorr5=0.D0
+ wcorr6=0.D0
+ wel_loc=0.D0
+ wturn3=0.D0
+ wturn4=0.D0
+ wturn6=0.D0
+ wang=0.D0
+ wtor=0.D0
+ wtor_d=0.D0
+
+! Prepare to freeze backbone
+ do i=1,nres
+ mask_phi(i)=0
+ mask_theta(i)=0
+ mask_side(i)=1
+ enddo
+
+! Minimize the side-chains
+ mask_r=.true.
+ call geom_to_var(nvar,var)
+ call minimize(etot,var,iretcode,nfun)
+ call var_to_geom(nvar,var)
+ mask_r=.false.
+
+! Put the original weights back and calculate the full energy
+ wscp=orig_w(2)
+ welec=orig_w(3)
+ wcorr=orig_w(4)
+ wcorr5=orig_w(5)
+ wcorr6=orig_w(6)
+ wel_loc=orig_w(7)
+ wturn3=orig_w(8)
+ wturn4=orig_w(9)
+ wturn6=orig_w(10)
+ wang=orig_w(11)
+ wtor=orig_w(13)
+ wtor_d=orig_w(14)
+
+ call chainbuild
+ call etotal(energy_)
+ etot=energy_(0)
+
+ return
+ end subroutine sc_minimize
+!-----------------------------------------------------------------------------
+ subroutine minimize_sc1(etot,x,iretcode,nfun)
+
+ use energy, only: func,gradient,fdum,etotal,enerprint
+ use comm_srutu
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+ integer,parameter :: liv=60
+ integer :: iretcode,nfun
+! integer :: lv=(77+(6*nres)*(6*nres+17)/2) !(77+maxvar*(maxvar+17)/2)) (maxvar=6*maxres)
+! include 'COMMON.IOUNITS'
+! include 'COMMON.VAR'
+! include 'COMMON.GEO'
+! include 'COMMON.MINIM'
+!el integer :: icall
+!el common /srutu/ icall
+ integer,dimension(liv) :: iv
+ real(kind=8) :: minval !,v(1:77+(6*nres)*(6*nres+17)/2) !(1:lv)
+ real(kind=8),dimension(6*nres) :: x,d,xx !(maxvar) (maxvar=6*maxres)
+ real(kind=8) :: energia(0:n_ene)
+!el real(kind=8) :: fdum
+! external gradient,fdum !func,
+! external func_restr1,grad_restr1
+ logical :: not_done,change,reduce
+!el common /przechowalnia/ v
+
+ integer :: nvar_restr,lv,i,j
+ integer :: idum(1)
+ real(kind=8) :: rdum(1),etot !,fdum
+
+ lv=(77+(6*nres)*(6*nres+17)/2) !(77+maxvar*(maxvar+17)/2)) (maxvar=6*maxres)
+ if (.not. allocated(v)) allocate(v(1:lv))
+
+ call deflt(2,iv,liv,lv,v)
+! 12 means fresh start, dont call deflt
+ iv(1)=12
+! max num of fun calls
+ if (maxfun.eq.0) maxfun=500
+ iv(17)=maxfun
+! max num of iterations
+ if (maxmin.eq.0) maxmin=1000
+ iv(18)=maxmin
+! controls output
+ iv(19)=2
+! selects output unit
+! iv(21)=iout
+ iv(21)=0
+! 1 means to print out result
+ iv(22)=0
+! 1 means to print out summary stats
+ iv(23)=0
+! 1 means to print initial x and d
+ iv(24)=0
+! min val for v(radfac) default is 0.1
+ v(24)=0.1D0
+! max val for v(radfac) default is 4.0
+ v(25)=2.0D0
+! v(25)=4.0D0
+! check false conv if (act fnctn decrease) .lt. v(26)*(exp decrease)
+! the sumsl default is 0.1
+ v(26)=0.1D0
+! false conv if (act fnctn decrease) .lt. v(34)
+! the sumsl default is 100*machep
+ v(34)=v(34)/100.0D0
+! absolute convergence
+ if (tolf.eq.0.0D0) tolf=1.0D-4
+ v(31)=tolf
+! relative convergence
+ if (rtolf.eq.0.0D0) rtolf=1.0D-4
+ v(32)=rtolf
+! controls initial step size
+ v(35)=1.0D-1
+! large vals of d correspond to small components of step
+ do i=1,nphi
+ d(i)=1.0D-1
+ enddo
+ do i=nphi+1,nvar
+ d(i)=1.0D-1
+ enddo
+!elmask_r=.false.
+ IF (mask_r) THEN
+ call x2xx(x,xx,nvar_restr)
+ call sumsl(nvar_restr,d,xx,func_restr1,grad_restr1,&
+ iv,liv,lv,v,idum,rdum,fdum)
+ call xx2x(x,xx)
+ ELSE
+ call sumsl(nvar,d,x,func,gradient,iv,liv,lv,v,idum,rdum,fdum)
+ ENDIF
+!el---------------------
+! write (iout,'(/a)') &
+! "Cartesian coordinates of the reference structure after SUMSL"
+! write (iout,'(a,3(3x,a5),5x,3(3x,a5))') &
+! "Residue","X(CA)","Y(CA)","Z(CA)","X(SC)","Y(SC)","Z(SC)"
+! do i=1,nres
+! write (iout,'(a3,1x,i3,3f8.3,5x,3f8.3)') &
+! restyp(itype(i)),i,(c(j,i),j=1,3),&
+! (c(j,i+nres),j=1,3)
+! enddo
+! call etotal(energia)
+! call enerprint(energia)
+!el----------------------------
+ etot=v(10)
+ iretcode=iv(1)
+ nfun=iv(6)
+
+ return
+ end subroutine minimize_sc1
+!-----------------------------------------------------------------------------
+ subroutine func_restr1(n,x,nf,f,uiparm,urparm,ufparm)
+
+ use comm_chu
+ use energy, only: zerograd,esc,sc_grad
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+! include 'COMMON.DERIV'
+! include 'COMMON.IOUNITS'
+! include 'COMMON.GEO'
+! include 'COMMON.FFIELD'
+! include 'COMMON.INTERACT'
+! include 'COMMON.TIME1'
+ integer :: n,nf,i,j
+!el common /chuju/ jjj
+ real(kind=8) :: energia(0:n_ene),evdw,escloc
+ real(kind=8) :: e1,e2,f
+ real(kind=8),external :: ufparm
+ integer :: uiparm(1)
+ real(kind=8) :: urparm(1)
+ real(kind=8),dimension(6*nres) :: x !(maxvar) (maxvar=6*maxres)
+ nfl=nf
+ icg=mod(nf,2)+1
+
+#ifdef OSF
+! Intercept NaNs in the coordinates, before calling etotal
+ x_sum=0.D0
+ do i=1,n
+ x_sum=x_sum+x(i)
+ enddo
+ FOUND_NAN=.false.
+ if (x_sum.ne.x_sum) then
+ write(iout,*)" *** func_restr1 : Found NaN in coordinates"
+ f=1.0D+73
+ FOUND_NAN=.true.
+ return
+ endif
+#endif
+
+ call var_to_geom_restr(n,x)
+ call zerograd
+ call chainbuild
+!d write (iout,*) 'ETOTAL called from FUNC'
+ call egb1(evdw)
+ call esc(escloc)
+ f=wsc*evdw+wscloc*escloc
+!d call etotal(energia(0))
+!d f=wsc*energia(1)+wscloc*energia(12)
+!d print *,f,evdw,escloc,energia(0)
+!
+! Sum up the components of the Cartesian gradient.
+!
+ do i=1,nct
+ do j=1,3
+ gradx(j,i,icg)=wsc*gvdwx(j,i)
+ enddo
+ enddo
+
+ return
+ end subroutine func_restr1
+!-----------------------------------------------------------------------------
+ subroutine grad_restr1(n,x,nf,g,uiparm,urparm,ufparm)
+
+ use energy, only: cartder,zerograd,esc,sc_grad
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+! include 'COMMON.CHAIN'
+! include 'COMMON.DERIV'
+! include 'COMMON.VAR'
+! include 'COMMON.INTERACT'
+! include 'COMMON.FFIELD'
+! include 'COMMON.IOUNITS'
+!el external ufparm
+ integer :: i,j,k,ind,n,nf,uiparm(1)
+ real(kind=8) :: f,urparm(1)
+ real(kind=8),dimension(6*nres) :: x,g !(maxvar) (maxvar=6*maxres)
+ integer :: ig,igall,ij
+ real(kind=8) :: gphii,gthetai,galphai,gomegai
+ real(kind=8),external :: ufparm
+
+ icg=mod(nf,2)+1
+ if (nf-nfl+1) 20,30,40
+ 20 call func_restr1(n,x,nf,f,uiparm,urparm,ufparm)
+! write (iout,*) 'grad 20'
+ if (nf.eq.0) return
+ goto 40
+ 30 call var_to_geom_restr(n,x)
+ call chainbuild
+!
+! Evaluate the derivatives of virtual bond lengths and SC vectors in variables.
+!
+ 40 call cartder
+!
+! Convert the Cartesian gradient into internal-coordinate gradient.
+!
+
+ ig=0
+ ind=nres-2
+ do i=2,nres-2
+ IF (mask_phi(i+2).eq.1) THEN
+ gphii=0.0D0
+ do j=i+1,nres-1
+ ind=ind+1
+ do k=1,3
+ gphii=gphii+dcdv(k+3,ind)*gradc(k,j,icg)
+ gphii=gphii+dxdv(k+3,ind)*gradx(k,j,icg)
+ enddo
+ enddo
+ ig=ig+1
+ g(ig)=gphii
+ ELSE
+ ind=ind+nres-1-i
+ ENDIF
+ enddo
+
+
+ ind=0
+ do i=1,nres-2
+ IF (mask_theta(i+2).eq.1) THEN
+ ig=ig+1
+ gthetai=0.0D0
+ do j=i+1,nres-1
+ ind=ind+1
+ do k=1,3
+ gthetai=gthetai+dcdv(k,ind)*gradc(k,j,icg)
+ gthetai=gthetai+dxdv(k,ind)*gradx(k,j,icg)
+ enddo
+ enddo
+ g(ig)=gthetai
+ ELSE
+ ind=ind+nres-1-i
+ ENDIF
+ enddo
+
+ do i=2,nres-1
+ if (itype(i).ne.10) then
+ IF (mask_side(i).eq.1) THEN
+ ig=ig+1
+ galphai=0.0D0
+ do k=1,3
+ galphai=galphai+dxds(k,i)*gradx(k,i,icg)
+ enddo
+ g(ig)=galphai
+ ENDIF
+ endif
+ enddo
+
+
+ do i=2,nres-1
+ if (itype(i).ne.10) then
+ IF (mask_side(i).eq.1) THEN
+ ig=ig+1
+ gomegai=0.0D0
+ do k=1,3
+ gomegai=gomegai+dxds(k+3,i)*gradx(k,i,icg)
+ enddo
+ g(ig)=gomegai
+ ENDIF
+ endif
+ enddo
+
+!
+! Add the components corresponding to local energy terms.
+!
+
+ ig=0
+ igall=0
+ do i=4,nres
+ igall=igall+1
+ if (mask_phi(i).eq.1) then
+ ig=ig+1
+ g(ig)=g(ig)+gloc(igall,icg)
+ endif
+ enddo
+
+ do i=3,nres
+ igall=igall+1
+ if (mask_theta(i).eq.1) then
+ ig=ig+1
+ g(ig)=g(ig)+gloc(igall,icg)
+ endif
+ enddo
+
+ do ij=1,2
+ do i=2,nres-1
+ if (itype(i).ne.10) then
+ igall=igall+1
+ if (mask_side(i).eq.1) then
+ ig=ig+1
+ g(ig)=g(ig)+gloc(igall,icg)
+ endif
+ endif
+ enddo
+ enddo
+
+!d do i=1,ig
+!d write (iout,'(a2,i5,a3,f25.8)') 'i=',i,' g=',g(i)
+!d enddo
+ return
+ end subroutine grad_restr1
+!-----------------------------------------------------------------------------
+ subroutine egb1(evdw)
+!
+! This subroutine calculates the interaction energy of nonbonded side chains
+! assuming the Gay-Berne potential of interaction.
+!
+ use calc_data
+ use energy, only: sc_grad
+! use control, only:stopx
+! implicit real*8 (a-h,o-z)
+! include 'DIMENSIONS'
+! include 'COMMON.GEO'
+! include 'COMMON.VAR'
+! include 'COMMON.LOCAL'
+! include 'COMMON.CHAIN'
+! include 'COMMON.DERIV'
+! include 'COMMON.NAMES'
+! include 'COMMON.INTERACT'
+! include 'COMMON.IOUNITS'
+! include 'COMMON.CALC'
+! include 'COMMON.CONTROL'
+ logical :: lprn
+ real(kind=8) :: evdw
+!el local variables
+ integer :: iint,ind,itypi,itypi1,itypj
+ real(kind=8) :: xi,yi,zi,rrij,sig,sig0ij,rij_shift,fac,e1,e2,&
+ sigm,epsi
+!elwrite(iout,*) "check evdw"
+! print *,'Entering EGB nnt=',nnt,' nct=',nct,' expon=',expon
+ evdw=0.0D0
+ lprn=.false.
+! if (icall.eq.0) lprn=.true.
+ ind=0
+ do i=iatsc_s,iatsc_e
+
+ itypi=iabs(itype(i))
+ itypi1=iabs(itype(i+1))
+ xi=c(1,nres+i)
+ yi=c(2,nres+i)
+ zi=c(3,nres+i)
+ dxi=dc_norm(1,nres+i)
+ dyi=dc_norm(2,nres+i)
+ dzi=dc_norm(3,nres+i)
+ dsci_inv=dsc_inv(itypi)
+!elwrite(iout,*) itypi,itypi1,xi,yi,zi,dxi,dyi,dzi,dsci_inv
+!
+! Calculate SC interaction energy.
+!
+ do iint=1,nint_gr(i)
+ do j=istart(i,iint),iend(i,iint)
+ IF (mask_side(j).eq.1.or.mask_side(i).eq.1) THEN
+ ind=ind+1
+ itypj=iabs(itype(j))
+ dscj_inv=dsc_inv(itypj)
+ sig0ij=sigma(itypi,itypj)
+ chi1=chi(itypi,itypj)
+ chi2=chi(itypj,itypi)
+ chi12=chi1*chi2
+ chip1=chip(itypi)
+ chip2=chip(itypj)
+ chip12=chip1*chip2
+ alf1=alp(itypi)
+ alf2=alp(itypj)
+ alf12=0.5D0*(alf1+alf2)
+! For diagnostics only!!!
+! chi1=0.0D0
+! chi2=0.0D0
+! chi12=0.0D0
+! chip1=0.0D0
+! chip2=0.0D0
+! chip12=0.0D0
+! alf1=0.0D0
+! alf2=0.0D0
+! alf12=0.0D0
+ xj=c(1,nres+j)-xi
+ yj=c(2,nres+j)-yi
+ zj=c(3,nres+j)-zi
+ dxj=dc_norm(1,nres+j)
+ dyj=dc_norm(2,nres+j)
+ dzj=dc_norm(3,nres+j)
+ rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
+ rij=dsqrt(rrij)
+! Calculate angle-dependent terms of energy and contributions to their
+! derivatives.
+ call sc_angular
+ sigsq=1.0D0/sigsq
+ sig=sig0ij*dsqrt(sigsq)
+ rij_shift=1.0D0/rij-sig+sig0ij
+! I hate to put IF's in the loops, but here don't have another choice!!!!
+ if (rij_shift.le.0.0D0) then
+ evdw=1.0D20
+!d write (iout,'(2(a3,i3,2x),17(0pf7.3))') &
+!d restyp(itypi),i,restyp(itypj),j, &
+!d rij_shift,1.0D0/rij,sig,sig0ij,sigsq,1-dsqrt(sigsq)
+ return
+ endif
+ sigder=-sig*sigsq
+!---------------------------------------------------------------
+ rij_shift=1.0D0/rij_shift
+ fac=rij_shift**expon
+ e1=fac*fac*aa(itypi,itypj)
+ e2=fac*bb(itypi,itypj)
+ evdwij=eps1*eps2rt*eps3rt*(e1+e2)
+ eps2der=evdwij*eps3rt
+ eps3der=evdwij*eps2rt
+ evdwij=evdwij*eps2rt*eps3rt
+ evdw=evdw+evdwij
+ if (lprn) then
+ sigm=dabs(aa(itypi,itypj)/bb(itypi,itypj))**(1.0D0/6.0D0)
+ epsi=bb(itypi,itypj)**2/aa(itypi,itypj)
+!d write (iout,'(2(a3,i3,2x),17(0pf7.3))') &
+!d restyp(itypi),i,restyp(itypj),j, &
+!d epsi,sigm,chi1,chi2,chip1,chip2, &
+!d eps1,eps2rt**2,eps3rt**2,sig,sig0ij, &
+!d om1,om2,om12,1.0D0/rij,1.0D0/rij_shift, &
+!d evdwij
+ endif
+
+ if (energy_dec) write (iout,'(a6,2i5,0pf7.3)') &
+ 'evdw',i,j,evdwij
+
+! Calculate gradient components.
+ e1=e1*eps1*eps2rt**2*eps3rt**2
+ fac=-expon*(e1+evdwij)*rij_shift
+ sigder=fac*sigder
+ fac=rij*fac
+! Calculate the radial part of the gradient
+ gg(1)=xj*fac
+ gg(2)=yj*fac
+ gg(3)=zj*fac
+! Calculate angular part of the gradient.
+
+!elwrite(iout,*) evdw
+ call sc_grad
+!elwrite(iout,*) "evdw=",evdw,j,iint,i
+ ENDIF
+!elwrite(iout,*) evdw
+ enddo ! j
+!elwrite(iout,*) evdw
+ enddo ! iint
+!elwrite(iout,*) evdw
+ enddo ! i
+!elwrite(iout,*) evdw,i
+ end subroutine egb1
+!-----------------------------------------------------------------------------
+! sumsld.f
+!-----------------------------------------------------------------------------
+ subroutine sumsl(n,d,x,calcf,calcg,iv,liv,lv,v,uiparm,urparm,ufparm)
+!
+! *** minimize general unconstrained objective function using ***
+! *** analytic gradient and hessian approx. from secant update ***
+!
+! use control
+ integer :: n, liv, lv
+ integer :: iv(liv), uiparm(1)
+ real(kind=8) :: d(n), x(n), v(lv), urparm(1)
+ real(kind=8),external :: ufparm !funtion name as an argument
+
+! dimension v(71 + n*(n+15)/2), uiparm(*), urparm(*)
+ external :: calcf, calcg !subroutine name as an argument
+!
+! *** purpose ***
+!
+! this routine interacts with subroutine sumit in an attempt
+! to find an n-vector x* that minimizes the (unconstrained)
+! objective function computed by calcf. (often the x* found is
+! a local minimizer rather than a global one.)
+!
+!-------------------------- parameter usage --------------------------
+!
+! n........ (input) the number of variables on which f depends, i.e.,
+! the number of components in x.
+! d........ (input/output) a scale vector such that d(i)*x(i),
+! i = 1,2,...,n, are all in comparable units.
+! d can strongly affect the behavior of sumsl.
+! finding the best choice of d is generally a trial-
+! and-error process. choosing d so that d(i)*x(i)
+! has about the same value for all i often works well.
+! the defaults provided by subroutine deflt (see i
+! below) require the caller to supply d.
+! x........ (input/output) before (initially) calling sumsl, the call-
+! er should set x to an initial guess at x*. when
+! sumsl returns, x contains the best point so far
+! found, i.e., the one that gives the least value so
+! far seen for f(x).
+! calcf.... (input) a subroutine that, given x, computes f(x). calcf
+! must be declared external in the calling program.
+! it is invoked by
+! call calcf(n, x, nf, f, uiparm, urparm, ufparm)
+! when calcf is called, nf is the invocation
+! count for calcf. nf is included for possible use
+! with calcg. if x is out of bounds (e.g., if it
+! would cause overflow in computing f(x)), then calcf
+! should set nf to 0. this will cause a shorter step
+! to be attempted. (if x is in bounds, then calcf
+! should not change nf.) the other parameters are as
+! described above and below. calcf should not change
+! n, p, or x.
+! calcg.... (input) a subroutine that, given x, computes g(x), the gra-
+! dient of f at x. calcg must be declared external in
+! the calling program. it is invoked by
+! call calcg(n, x, nf, g, uiparm, urparm, ufaprm)
+! when calcg is called, nf is the invocation
+! count for calcf at the time f(x) was evaluated. the
+! x passed to calcg is usually the one passed to calcf
+! on either its most recent invocation or the one
+! prior to it. if calcf saves intermediate results
+! for use by calcg, then it is possible to tell from
+! nf whether they are valid for the current x (or
+! which copy is valid if two copies are kept). if g
+! cannot be computed at x, then calcg should set nf to
+! 0. in this case, sumsl will return with iv(1) = 65.
+! (if g can be computed at x, then calcg should not
+! changed nf.) the other parameters to calcg are as
+! described above and below. calcg should not change
+! n or x.
+! iv....... (input/output) an integer value array of length liv (see
+! below) that helps control the sumsl algorithm and
+! that is used to store various intermediate quanti-
+! ties. of particular interest are the initialization/
+! return code iv(1) and the entries in iv that control
+! printing and limit the number of iterations and func-
+! tion evaluations. see the section on iv input
+! values below.
+! liv...... (input) length of iv array. must be at least 60. if li
+! is too small, then sumsl returns with iv(1) = 15.
+! when sumsl returns, the smallest allowed value of
+! liv is stored in iv(lastiv) -- see the section on
+! iv output values below. (this is intended for use
+! with extensions of sumsl that handle constraints.)
+! lv....... (input) length of v array. must be at least 71+n*(n+15)/2.
+! (at least 77+n*(n+17)/2 for smsno, at least
+! 78+n*(n+12) for humsl). if lv is too small, then
+! sumsl returns with iv(1) = 16. when sumsl returns,
+! the smallest allowed value of lv is stored in
+! iv(lastv) -- see the section on iv output values
+! below.
+! v........ (input/output) a floating-point value array of length l
+! (see below) that helps control the sumsl algorithm
+! and that is used to store various intermediate
+! quantities. of particular interest are the entries
+! in v that limit the length of the first step
+! attempted (lmax0) and specify convergence tolerances
+! (afctol, lmaxs, rfctol, sctol, xctol, xftol).
+! uiparm... (input) user integer parameter array passed without change
+! to calcf and calcg.
+! urparm... (input) user floating-point parameter array passed without
+! change to calcf and calcg.
+! ufparm... (input) user external subroutine or function passed without
+! change to calcf and calcg.
+!
+! *** iv input values (from subroutine deflt) ***
+!
+! iv(1)... on input, iv(1) should have a value between 0 and 14......
+! 0 and 12 mean this is a fresh start. 0 means that
+! deflt(2, iv, liv, lv, v)
+! is to be called to provide all default values to iv and
+! v. 12 (the value that deflt assigns to iv(1)) means the
+! caller has already called deflt and has possibly changed
+! some iv and/or v entries to non-default values.
+! 13 means deflt has been called and that sumsl (and
+! sumit) should only do their storage allocation. that is,
+! they should set the output components of iv that tell
+! where various subarrays arrays of v begin, such as iv(g)
+! (and, for humsl and humit only, iv(dtol)), and return.
+! 14 means that a storage has been allocated (by a call
+! with iv(1) = 13) and that the algorithm should be
+! started. when called with iv(1) = 13, sumsl returns
+! iv(1) = 14 unless liv or lv is too small (or n is not
+! positive). default = 12.
+! iv(inith).... iv(25) tells whether the hessian approximation h should
+! be initialized. 1 (the default) means sumit should
+! initialize h to the diagonal matrix whose i-th diagonal
+! element is d(i)**2. 0 means the caller has supplied a
+! cholesky factor l of the initial hessian approximation
+! h = l*(l**t) in v, starting at v(iv(lmat)) = v(iv(42))
+! (and stored compactly by rows). note that iv(lmat) may
+! be initialized by calling sumsl with iv(1) = 13 (see
+! the iv(1) discussion above). default = 1.
+! iv(mxfcal)... iv(17) gives the maximum number of function evaluations
+! (calls on calcf) allowed. if this number does not suf-
+! fice, then sumsl returns with iv(1) = 9. default = 200.
+! iv(mxiter)... iv(18) gives the maximum number of iterations allowed.
+! it also indirectly limits the number of gradient evalua-
+! tions (calls on calcg) to iv(mxiter) + 1. if iv(mxiter)
+! iterations do not suffice, then sumsl returns with
+! iv(1) = 10. default = 150.
+! iv(outlev)... iv(19) controls the number and length of iteration sum-
+! mary lines printed (by itsum). iv(outlev) = 0 means do
+! not print any summary lines. otherwise, print a summary
+! line after each abs(iv(outlev)) iterations. if iv(outlev)
+! is positive, then summary lines of length 78 (plus carri-
+! age control) are printed, including the following... the
+! iteration and function evaluation counts, f = the current
+! function value, relative difference in function values
+! achieved by the latest step (i.e., reldf = (f0-v(f))/f01,
+! where f01 is the maximum of abs(v(f)) and abs(v(f0)) and
+! v(f0) is the function value from the previous itera-
+! tion), the relative function reduction predicted for the
+! step just taken (i.e., preldf = v(preduc) / f01, where
+! v(preduc) is described below), the scaled relative change
+! in x (see v(reldx) below), the step parameter for the
+! step just taken (stppar = 0 means a full newton step,
+! between 0 and 1 means a relaxed newton step, between 1
+! and 2 means a double dogleg step, greater than 2 means
+! a scaled down cauchy step -- see subroutine dbldog), the
+! 2-norm of the scale vector d times the step just taken
+! (see v(dstnrm) below), and npreldf, i.e.,
+! v(nreduc)/f01, where v(nreduc) is described below -- if
+! npreldf is positive, then it is the relative function
+! reduction predicted for a newton step (one with
+! stppar = 0). if npreldf is negative, then it is the
+! negative of the relative function reduction predicted
+! for a step computed with step bound v(lmaxs) for use in
+! testing for singular convergence.
+! if iv(outlev) is negative, then lines of length 50
+! are printed, including only the first 6 items listed
+! above (through reldx).
+! default = 1.
+! iv(parprt)... iv(20) = 1 means print any nondefault v values on a
+! fresh start or any changed v values on a restart.
+! iv(parprt) = 0 means skip this printing. default = 1.
+! iv(prunit)... iv(21) is the output unit number on which all printing
+! is done. iv(prunit) = 0 means suppress all printing.
+! default = standard output unit (unit 6 on most systems).
+! iv(solprt)... iv(22) = 1 means print out the value of x returned (as
+! well as the gradient and the scale vector d).
+! iv(solprt) = 0 means skip this printing. default = 1.
+! iv(statpr)... iv(23) = 1 means print summary statistics upon return-
+! ing. these consist of the function value, the scaled
+! relative change in x caused by the most recent step (see
+! v(reldx) below), the number of function and gradient
+! evaluations (calls on calcf and calcg), and the relative
+! function reductions predicted for the last step taken and
+! for a newton step (or perhaps a step bounded by v(lmaxs)
+! -- see the descriptions of preldf and npreldf under
+! iv(outlev) above).
+! iv(statpr) = 0 means skip this printing.
+! iv(statpr) = -1 means skip this printing as well as that
+! of the one-line termination reason message. default = 1.
+! iv(x0prt).... iv(24) = 1 means print the initial x and scale vector d
+! (on a fresh start only). iv(x0prt) = 0 means skip this
+! printing. default = 1.
+!
+! *** (selected) iv output values ***
+!
+! iv(1)........ on output, iv(1) is a return code....
+! 3 = x-convergence. the scaled relative difference (see
+! v(reldx)) between the current parameter vector x and
+! a locally optimal parameter vector is very likely at
+! most v(xctol).
+! 4 = relative function convergence. the relative differ-
+! ence between the current function value and its lo-
+! cally optimal value is very likely at most v(rfctol).
+! 5 = both x- and relative function convergence (i.e., the
+! conditions for iv(1) = 3 and iv(1) = 4 both hold).
+! 6 = absolute function convergence. the current function
+! value is at most v(afctol) in absolute value.
+! 7 = singular convergence. the hessian near the current
+! iterate appears to be singular or nearly so, and a
+! step of length at most v(lmaxs) is unlikely to yield
+! a relative function decrease of more than v(sctol).
+! 8 = false convergence. the iterates appear to be converg-
+! ing to a noncritical point. this may mean that the
+! convergence tolerances (v(afctol), v(rfctol),
+! v(xctol)) are too small for the accuracy to which
+! the function and gradient are being computed, that
+! there is an error in computing the gradient, or that
+! the function or gradient is discontinuous near x.
+! 9 = function evaluation limit reached without other con-
+! vergence (see iv(mxfcal)).
+! 10 = iteration limit reached without other convergence
+! (see iv(mxiter)).
+! 11 = stopx returned .true. (external interrupt). see the
+! usage notes below.
+! 14 = storage has been allocated (after a call with
+! iv(1) = 13).
+! 17 = restart attempted with n changed.
+! 18 = d has a negative component and iv(dtype) .le. 0.
+! 19...43 = v(iv(1)) is out of range.
+! 63 = f(x) cannot be computed at the initial x.
+! 64 = bad parameters passed to assess (which should not
+! occur).
+! 65 = the gradient could not be computed at x (see calcg
+! above).
+! 67 = bad first parameter to deflt.
+! 80 = iv(1) was out of range.
+! 81 = n is not positive.
+! iv(g)........ iv(28) is the starting subscript in v of the current
+! gradient vector (the one corresponding to x).
+! iv(lastiv)... iv(44) is the least acceptable value of liv. (it is
+! only set if liv is at least 44.)
+! iv(lastv).... iv(45) is the least acceptable value of lv. (it is
+! only set if liv is large enough, at least iv(lastiv).)
+! iv(nfcall)... iv(6) is the number of calls so far made on calcf (i.e.,
+! function evaluations).
+! iv(ngcall)... iv(30) is the number of gradient evaluations (calls on
+! calcg).
+! iv(niter).... iv(31) is the number of iterations performed.
+!
+! *** (selected) v input values (from subroutine deflt) ***
+!
+! v(bias)..... v(43) is the bias parameter used in subroutine dbldog --
+! see that subroutine for details. default = 0.8.
+! v(afctol)... v(31) is the absolute function convergence tolerance.
+! if sumsl finds a point where the function value is less
+! than v(afctol) in absolute value, and if sumsl does not
+! return with iv(1) = 3, 4, or 5, then it returns with
+! iv(1) = 6. this test can be turned off by setting
+! v(afctol) to zero. default = max(10**-20, machep**2),
+! where machep is the unit roundoff.
+! v(dinit).... v(38), if nonnegative, is the value to which the scale
+! vector d is initialized. default = -1.
+! v(lmax0).... v(35) gives the maximum 2-norm allowed for d times the
+! very first step that sumsl attempts. this parameter can
+! markedly affect the performance of sumsl.
+! v(lmaxs).... v(36) is used in testing for singular convergence -- if
+! the function reduction predicted for a step of length
+! bounded by v(lmaxs) is at most v(sctol) * abs(f0), where
+! f0 is the function value at the start of the current
+! iteration, and if sumsl does not return with iv(1) = 3,
+! 4, 5, or 6, then it returns with iv(1) = 7. default = 1.
+! v(rfctol)... v(32) is the relative function convergence tolerance.
+! if the current model predicts a maximum possible function
+! reduction (see v(nreduc)) of at most v(rfctol)*abs(f0)
+! at the start of the current iteration, where f0 is the
+! then current function value, and if the last step attempt-
+! ed achieved no more than twice the predicted function
+! decrease, then sumsl returns with iv(1) = 4 (or 5).
+! default = max(10**-10, machep**(2/3)), where machep is
+! the unit roundoff.
+! v(sctol).... v(37) is the singular convergence tolerance -- see the
+! description of v(lmaxs) above.
+! v(tuner1)... v(26) helps decide when to check for false convergence.
+! this is done if the actual function decrease from the
+! current step is no more than v(tuner1) times its predict-
+! ed value. default = 0.1.
+! v(xctol).... v(33) is the x-convergence tolerance. if a newton step
+! (see v(nreduc)) is tried that has v(reldx) .le. v(xctol)
+! and if this step yields at most twice the predicted func-
+! tion decrease, then sumsl returns with iv(1) = 3 (or 5).
+! (see the description of v(reldx) below.)
+! default = machep**0.5, where machep is the unit roundoff.
+! v(xftol).... v(34) is the false convergence tolerance. if a step is
+! tried that gives no more than v(tuner1) times the predict-
+! ed function decrease and that has v(reldx) .le. v(xftol),
+! and if sumsl does not return with iv(1) = 3, 4, 5, 6, or
+! 7, then it returns with iv(1) = 8. (see the description
+! of v(reldx) below.) default = 100*machep, where
+! machep is the unit roundoff.
+! v(*)........ deflt supplies to v a number of tuning constants, with
+! which it should ordinarily be unnecessary to tinker. see
+! section 17 of version 2.2 of the nl2sol usage summary
+! (i.e., the appendix to ref. 1) for details on v(i),
+! i = decfac, incfac, phmnfc, phmxfc, rdfcmn, rdfcmx,
+! tuner2, tuner3, tuner4, tuner5.
+!
+! *** (selected) v output values ***
+!
+! v(dgnorm)... v(1) is the 2-norm of (diag(d)**-1)*g, where g is the
+! most recently computed gradient.
+! v(dstnrm)... v(2) is the 2-norm of diag(d)*step, where step is the
+! current step.
+! v(f)........ v(10) is the current function value.
+! v(f0)....... v(13) is the function value at the start of the current
+! iteration.
+! v(nreduc)... v(6), if positive, is the maximum function reduction
+! possible according to the current model, i.e., the func-
+! tion reduction predicted for a newton step (i.e.,
+! step = -h**-1 * g, where g is the current gradient and
+! h is the current hessian approximation).
+! if v(nreduc) is negative, then it is the negative of
+! the function reduction predicted for a step computed with
+! a step bound of v(lmaxs) for use in testing for singular
+! convergence.
+! v(preduc)... v(7) is the function reduction predicted (by the current
+! quadratic model) for the current step. this (divided by
+! v(f0)) is used in testing for relative function
+! convergence.
+! v(reldx).... v(17) is the scaled relative change in x caused by the
+! current step, computed as
+! max(abs(d(i)*(x(i)-x0(i)), 1 .le. i .le. p) /
+! max(d(i)*(abs(x(i))+abs(x0(i))), 1 .le. i .le. p),
+! where x = x0 + step.
+!
+!------------------------------- notes -------------------------------
+!
+! *** algorithm notes ***
+!
+! this routine uses a hessian approximation computed from the
+! bfgs update (see ref 3). only a cholesky factor of the hessian
+! approximation is stored, and this is updated using ideas from
+! ref. 4. steps are computed by the double dogleg scheme described
+! in ref. 2. the steps are assessed as in ref. 1.
+!
+! *** usage notes ***
+!
+! after a return with iv(1) .le. 11, it is possible to restart,
+! i.e., to change some of the iv and v input values described above
+! and continue the algorithm from the point where it was interrupt-
+! ed. iv(1) should not be changed, nor should any entries of i
+! and v other than the input values (those supplied by deflt).
+! those who do not wish to write a calcg which computes the
+! gradient analytically should call smsno rather than sumsl.
+! smsno uses finite differences to compute an approximate gradient.
+! those who would prefer to provide f and g (the function and
+! gradient) by reverse communication rather than by writing subrou-
+! tines calcf and calcg may call on sumit directly. see the com-
+! ments at the beginning of sumit.
+! those who use sumsl interactively may wish to supply their
+! own stopx function, which should return .true. if the break key
+! has been pressed since stopx was last invoked. this makes it
+! possible to externally interrupt sumsl (which will return with
+! iv(1) = 11 if stopx returns .true.).
+! storage for g is allocated at the end of v. thus the caller
+! may make v longer than specified above and may allow calcg to use
+! elements of g beyond the first n as scratch storage.
+!
+! *** portability notes ***
+!
+! the sumsl distribution tape contains both single- and double-
+! precision versions of the sumsl source code, so it should be un-
+! necessary to change precisions.
+! only the functions imdcon and rmdcon contain machine-dependent
+! constants. to change from one machine to another, it should
+! suffice to change the (few) relevant lines in these functions.
+! intrinsic functions are explicitly declared. on certain com-
+! puters (e.g. univac), it may be necessary to comment out these
+! declarations. so that this may be done automatically by a simple
+! program, such declarations are preceded by a comment having c/+
+! in columns 1-3 and blanks in columns 4-72 and are followed by
+! a comment having c/ in columns 1 and 2 and blanks in columns 3-72.
+! the sumsl source code is expressed in 1966 ansi standard
+! fortran. it may be converted to fortran 77 by commenting out all
+! lines that fall between a line having c/6 in columns 1-3 and a
+! line having c/7 in columns 1-3 and by removing (i.e., replacing
+! by a blank) the c in column 1 of the lines that follow the c/7
+! line and precede a line having c/ in columns 1-2 and blanks in
+! columns 3-72. these changes convert some data statements into
+! parameter statements, convert some variables from real to
+! character*4, and make the data statements that initialize these
+! variables use character strings delimited by primes instead
+! of hollerith constants. (such variables and data statements
+! appear only in modules itsum and parck. parameter statements
+! appear nearly everywhere.) these changes also add save state-
+! ments for variables given machine-dependent constants by rmdcon.
+!
+! *** references ***
+!
+! 1. dennis, j.e., gay, d.m., and welsch, r.e. (1981), algorithm 573 --
+! an adaptive nonlinear least-squares algorithm, acm trans.
+! math. software 7, pp. 369-383.
+!
+! 2. dennis, j.e., and mei, h.h.w. (1979), two new unconstrained opti-
+! mization algorithms which use function and gradient
+! values, j. optim. theory applic. 28, pp. 453-482.
+!
+! 3. dennis, j.e., and more, j.j. (1977), quasi-newton methods, motiva-
+! tion and theory, siam rev. 19, pp. 46-89.
+!
+! 4. goldfarb, d. (1976), factorized variable metric methods for uncon-
+! strained optimization, math. comput. 30, pp. 796-811.
+!
+! *** general ***
+!
+! coded by david m. gay (winter 1980). revised summer 1982.
+! this subroutine was written in connection with research
+! supported in part by the national science foundation under
+! grants mcs-7600324, dcr75-10143, 76-14311dss, mcs76-11989,
+! and mcs-7906671.
+!.
+!
+!---------------------------- declarations ---------------------------
+!
+!el external deflt, sumit
+!
+! deflt... supplies default iv and v input components.
+! sumit... reverse-communication routine that carries out sumsl algo-
+! rithm.
+!
+ integer :: g1, iv1, nf
+ real(kind=8) :: f
+!
+! *** subscripts for iv ***
+!
+!el integer nextv, nfcall, nfgcal, g, toobig, vneed
+!
+!/6
+! data nextv/47/, nfcall/6/, nfgcal/7/, g/28/, toobig/2/, vneed/4/
+!/7
+ integer,parameter :: nextv=47, nfcall=6, nfgcal=7, g=28,&
+ toobig=2, vneed=4
+!/
+!
+!+++++++++++++++++++++++++++++++ body ++++++++++++++++++++++++++++++++
+!
+!elwrite(iout,*) "in sumsl"
+ if (iv(1) .eq. 0) call deflt(2, iv, liv, lv, v)
+ iv1 = iv(1)
+ if (iv1 .eq. 12 .or. iv1 .eq. 13) iv(vneed) = iv(vneed) + n
+ if (iv1 .eq. 14) go to 10
+ if (iv1 .gt. 2 .and. iv1 .lt. 12) go to 10
+ g1 = 1
+ if (iv1 .eq. 12) iv(1) = 13
+ go to 20
+!
+ 10 g1 = iv(g)
+!elwrite(iout,*) "in sumsl go to 10"
+
+!
+!elwrite(iout,*) "in sumsl"
+ 20 call sumit(d, f, v(g1), iv, liv, lv, n, v, x)
+!elwrite(iout,*) "in sumsl, go to 20"
+
+!elwrite(iout,*) "in sumsl, go to 20, po sumit"
+!elwrite(iout,*) "in sumsl iv()", iv(1)-2
+ if (iv(1) - 2) 30, 40, 50
+!
+ 30 nf = iv(nfcall)
+!elwrite(iout,*) "in sumsl iv",iv(nfcall)
+ call calcf(n, x, nf, f, uiparm, urparm, ufparm)
+!elwrite(iout,*) "in sumsl"
+ if (nf .le. 0) iv(toobig) = 1
+ go to 20
+!
+!elwrite(iout,*) "in sumsl"
+ 40 call calcg(n, x, iv(nfgcal), v(g1), uiparm, urparm, ufparm)
+!elwrite(iout,*) "in sumsl"
+ go to 20
+!
+ 50 if (iv(1) .ne. 14) go to 999
+!
+! *** storage allocation
+!
+ iv(g) = iv(nextv)
+ iv(nextv) = iv(g) + n
+ if (iv1 .ne. 13) go to 10
+!elwrite(iout,*) "in sumsl"
+!
+ 999 return
+! *** last card of sumsl follows ***
+ end subroutine sumsl
+!-----------------------------------------------------------------------------
+ subroutine sumit(d,fx,g,iv,liv,lv,n,v,x)
+
+ use control, only:stopx
+!
+! *** carry out sumsl (unconstrained minimization) iterations, using
+! *** double-dogleg/bfgs steps.
+!
+! *** parameter declarations ***
+!
+ integer :: liv, lv, n
+ integer :: iv(liv)
+ real(kind=8) :: d(n), fx, g(n), v(lv), x(n)
+!
+!-------------------------- parameter usage --------------------------
+!
+! d.... scale vector.
+! fx... function value.
+! g.... gradient vector.
+! iv... integer value array.
+! liv.. length of iv (at least 60).
+! lv... length of v (at least 71 + n*(n+13)/2).
+! n.... number of variables (components in x and g).
+! v.... floating-point value array.
+! x.... vector of parameters to be optimized.
+!
+! *** discussion ***
+!
+! parameters iv, n, v, and x are the same as the corresponding
+! ones to sumsl (which see), except that v can be shorter (since
+! the part of v that sumsl uses for storing g is not needed).
+! moreover, compared with sumsl, iv(1) may have the two additional
+! output values 1 and 2, which are explained below, as is the use
+! of iv(toobig) and iv(nfgcal). the value iv(g), which is an
+! output value from sumsl (and smsno), is not referenced by
+! sumit or the subroutines it calls.
+! fx and g need not have been initialized when sumit is called
+! with iv(1) = 12, 13, or 14.
+!
+! iv(1) = 1 means the caller should set fx to f(x), the function value
+! at x, and call sumit again, having changed none of the
+! other parameters. an exception occurs if f(x) cannot be
+! (e.g. if overflow would occur), which may happen because
+! of an oversized step. in this case the caller should set
+! iv(toobig) = iv(2) to 1, which will cause sumit to ig-
+! nore fx and try a smaller step. the parameter nf that
+! sumsl passes to calcf (for possible use by calcg) is a
+! copy of iv(nfcall) = iv(6).
+! iv(1) = 2 means the caller should set g to g(x), the gradient vector
+! of f at x, and call sumit again, having changed none of
+! the other parameters except possibly the scale vector d
+! when iv(dtype) = 0. the parameter nf that sumsl passes
+! to calcg is iv(nfgcal) = iv(7). if g(x) cannot be
+! evaluated, then the caller may set iv(nfgcal) to 0, in
+! which case sumit will return with iv(1) = 65.
+!.
+! *** general ***
+!
+! coded by david m. gay (december 1979). revised sept. 1982.
+! this subroutine was written in connection with research supported
+! in part by the national science foundation under grants
+! mcs-7600324 and mcs-7906671.
+!
+! (see sumsl for references.)
+!
+!+++++++++++++++++++++++++++ declarations ++++++++++++++++++++++++++++
+!
+! *** local variables ***
+!
+ integer :: dg1, dummy, g01, i, k, l, lstgst, nwtst1, step1,&
+ temp1, w, x01, z
+ real(kind=8) :: t
+!el logical :: lstopx
+!
+! *** constants ***
+!
+!el real(kind=8) :: half, negone, one, onep2, zero
+!
+! *** no intrinsic functions ***
+!
+! *** external functions and subroutines ***
+!
+!el external assst, dbdog, deflt, dotprd, itsum, litvmu, livmul,
+!el 1 ltvmul, lupdat, lvmul, parck, reldst, stopx, vaxpy,
+!el 2 vcopy, vscopy, vvmulp, v2norm, wzbfgs
+!el logical stopx
+!el real(kind=8) :: dotprd, reldst, v2norm
+!
+! assst.... assesses candidate step.
+! dbdog.... computes double-dogleg (candidate) step.
+! deflt.... supplies default iv and v input components.
+! dotprd... returns inner product of two vectors.
+! itsum.... prints iteration summary and info on initial and final x.
+! litvmu... multiplies inverse transpose of lower triangle times vector.
+! livmul... multiplies inverse of lower triangle times vector.
+! ltvmul... multiplies transpose of lower triangle times vector.
+! lupdt.... updates cholesky factor of hessian approximation.
+! lvmul.... multiplies lower triangle times vector.
+! parck.... checks validity of input iv and v values.
+! reldst... computes v(reldx) = relative step size.
+! stopx.... returns .true. if the break key has been pressed.
+! vaxpy.... computes scalar times one vector plus another.
+! vcopy.... copies one vector to another.
+! vscopy... sets all elements of a vector to a scalar.
+! vvmulp... multiplies vector by vector raised to power (componentwise).
+! v2norm... returns the 2-norm of a vector.
+! wzbfgs... computes w and z for lupdat corresponding to bfgs update.
+!
+! *** subscripts for iv and v ***
+!
+!el integer afctol
+!el integer cnvcod, dg, dgnorm, dinit, dstnrm, dst0, f, f0, fdif,
+!el 1 gthg, gtstep, g0, incfac, inith, irc, kagqt, lmat, lmax0,
+!el 2 lmaxs, mode, model, mxfcal, mxiter, nextv, nfcall, nfgcal,
+!el 3 ngcall, niter, nreduc, nwtstp, preduc, radfac, radinc,
+!el 4 radius, rad0, reldx, restor, step, stglim, stlstg, toobig,
+!el 5 tuner4, tuner5, vneed, xirc, x0
+!
+! *** iv subscript values ***
+!
+!/6
+! data cnvcod/55/, dg/37/, g0/48/, inith/25/, irc/29/, kagqt/33/,
+! 1 mode/35/, model/5/, mxfcal/17/, mxiter/18/, nfcall/6/,
+! 2 nfgcal/7/, ngcall/30/, niter/31/, nwtstp/34/, radinc/8/,
+! 3 restor/9/, step/40/, stglim/11/, stlstg/41/, toobig/2/,
+! 4 vneed/4/, xirc/13/, x0/43/
+!/7
+ integer,parameter :: cnvcod=55, dg=37, g0=48, inith=25, irc=29, kagqt=33,&
+ mode=35, model=5, mxfcal=17, mxiter=18, nfcall=6,&
+ nfgcal=7, ngcall=30, niter=31, nwtstp=34, radinc=8,&
+ restor=9, step=40, stglim=11, stlstg=41, toobig=2,&
+ vneed=4, xirc=13, x0=43
+!/
+!
+! *** v subscript values ***
+!
+!/6
+! data afctol/31/
+! data dgnorm/1/, dinit/38/, dstnrm/2/, dst0/3/, f/10/, f0/13/,
+! 1 fdif/11/, gthg/44/, gtstep/4/, incfac/23/, lmat/42/,
+! 2 lmax0/35/, lmaxs/36/, nextv/47/, nreduc/6/, preduc/7/,
+! 3 radfac/16/, radius/8/, rad0/9/, reldx/17/, tuner4/29/,
+! 4 tuner5/30/
+!/7
+ integer,parameter :: afctol=31
+ integer,parameter :: dgnorm=1, dinit=38, dstnrm=2, dst0=3, f=10, f0=13,&
+ fdif=11, gthg=44, gtstep=4, incfac=23, lmat=42,&
+ lmax0=35, lmaxs=36, nextv=47, nreduc=6, preduc=7,&
+ radfac=16, radius=8, rad0=9, reldx=17, tuner4=29,&
+ tuner5=30
+!/
+!
+!/6
+! data half/0.5d+0/, negone/-1.d+0/, one/1.d+0/, onep2/1.2d+0/,
+! 1 zero/0.d+0/
+!/7
+ real(kind=8),parameter :: half=0.5d+0, negone=-1.d+0, one=1.d+0,&
+ onep2=1.2d+0,zero=0.d+0
+!/
+!
+!+++++++++++++++++++++++++++++++ body ++++++++++++++++++++++++++++++++
+!
+! Following SAVE statement inserted.
+ save l
+ i = iv(1)
+ if (i .eq. 1) go to 50
+ if (i .eq. 2) go to 60
+!
+! *** check validity of iv and v input values ***
+!
+ if (iv(1) .eq. 0) call deflt(2, iv, liv, lv, v)
+ if (iv(1) .eq. 12 .or. iv(1) .eq. 13) &
+ iv(vneed) = iv(vneed) + n*(n+13)/2
+ call parck(2, d, iv, liv, lv, n, v)
+ i = iv(1) - 2
+ if (i .gt. 12) go to 999
+ go to (180, 180, 180, 180, 180, 180, 120, 90, 120, 10, 10, 20), i
+!
+! *** storage allocation ***
+!
+10 l = iv(lmat)
+ iv(x0) = l + n*(n+1)/2
+ iv(step) = iv(x0) + n
+ iv(stlstg) = iv(step) + n
+ iv(g0) = iv(stlstg) + n
+ iv(nwtstp) = iv(g0) + n
+ iv(dg) = iv(nwtstp) + n
+ iv(nextv) = iv(dg) + n
+ if (iv(1) .ne. 13) go to 20
+ iv(1) = 14
+ go to 999
+!
+! *** initialization ***
+!
+ 20 iv(niter) = 0
+ iv(nfcall) = 1
+ iv(ngcall) = 1
+ iv(nfgcal) = 1
+ iv(mode) = -1
+ iv(model) = 1
+ iv(stglim) = 1
+ iv(toobig) = 0
+ iv(cnvcod) = 0
+ iv(radinc) = 0
+ v(rad0) = zero
+ if (v(dinit) .ge. zero) call vscopy(n, d, v(dinit))
+ if (iv(inith) .ne. 1) go to 40
+!
+! *** set the initial hessian approximation to diag(d)**-2 ***
+!
+ l = iv(lmat)
+ call vscopy(n*(n+1)/2, v(l), zero)
+ k = l - 1
+ do 30 i = 1, n
+ k = k + i
+ t = d(i)
+ if (t .le. zero) t = one
+ v(k) = t
+ 30 continue
+!
+! *** compute initial function value ***
+!
+ 40 iv(1) = 1
+ go to 999
+!
+ 50 v(f) = fx
+ if (iv(mode) .ge. 0) go to 180
+ iv(1) = 2
+ if (iv(toobig) .eq. 0) go to 999
+ iv(1) = 63
+ go to 300
+!
+! *** make sure gradient could be computed ***
+!
+ 60 if (iv(nfgcal) .ne. 0) go to 70
+ iv(1) = 65
+ go to 300
+!
+ 70 dg1 = iv(dg)
+ call vvmulp(n, v(dg1), g, d, -1)
+ v(dgnorm) = v2norm(n, v(dg1))
+!
+! *** test norm of gradient ***
+!
+ if (v(dgnorm) .gt. v(afctol)) go to 75
+ iv(irc) = 10
+ iv(cnvcod) = iv(irc) - 4
+!
+ 75 if (iv(cnvcod) .ne. 0) go to 290
+ if (iv(mode) .eq. 0) go to 250
+!
+! *** allow first step to have scaled 2-norm at most v(lmax0) ***
+!
+ v(radius) = v(lmax0)
+!
+ iv(mode) = 0
+!
+!
+!----------------------------- main loop -----------------------------
+!
+!
+! *** print iteration summary, check iteration limit ***
+!
+ 80 call itsum(d, g, iv, liv, lv, n, v, x)
+ 90 k = iv(niter)
+ if (k .lt. iv(mxiter)) go to 100
+ iv(1) = 10
+ go to 300
+!
+! *** update radius ***
+!
+ 100 iv(niter) = k + 1
+ if(k.gt.0)v(radius) = v(radfac) * v(dstnrm)
+!
+! *** initialize for start of next iteration ***
+!
+ g01 = iv(g0)
+ x01 = iv(x0)
+ v(f0) = v(f)
+ iv(irc) = 4
+ iv(kagqt) = -1
+!
+! *** copy x to x0, g to g0 ***
+!
+ call vcopy(n, v(x01), x)
+ call vcopy(n, v(g01), g)
+!
+! *** check stopx and function evaluation limit ***
+!
+! AL 4/30/95
+ dummy=iv(nfcall)
+!el lstopx = stopx(dummy)
+!elwrite(iout,*) "lstopx",lstopx,dummy
+ 110 if (.not. stopx(dummy)) go to 130
+ iv(1) = 11
+! write (iout,*) "iv(1)=11 !!!!"
+ go to 140
+!
+! *** come here when restarting after func. eval. limit or stopx.
+!
+ 120 if (v(f) .ge. v(f0)) go to 130
+ v(radfac) = one
+ k = iv(niter)
+ go to 100
+!
+ 130 if (iv(nfcall) .lt. iv(mxfcal)) go to 150
+ iv(1) = 9
+ 140 if (v(f) .ge. v(f0)) go to 300
+!
+! *** in case of stopx or function evaluation limit with
+! *** improved v(f), evaluate the gradient at x.
+!
+ iv(cnvcod) = iv(1)
+ go to 240
+!
+!. . . . . . . . . . . . . compute candidate step . . . . . . . . . .
+!
+ 150 step1 = iv(step)
+ dg1 = iv(dg)
+ nwtst1 = iv(nwtstp)
+ if (iv(kagqt) .ge. 0) go to 160
+ l = iv(lmat)
+ call livmul(n, v(nwtst1), v(l), g)
+ v(nreduc) = half * dotprd(n, v(nwtst1), v(nwtst1))
+ call litvmu(n, v(nwtst1), v(l), v(nwtst1))
+ call vvmulp(n, v(step1), v(nwtst1), d, 1)
+ v(dst0) = v2norm(n, v(step1))
+ call vvmulp(n, v(dg1), v(dg1), d, -1)
+ call ltvmul(n, v(step1), v(l), v(dg1))
+ v(gthg) = v2norm(n, v(step1))
+ iv(kagqt) = 0
+ 160 call dbdog(v(dg1), lv, n, v(nwtst1), v(step1), v)
+ if (iv(irc) .eq. 6) go to 180
+!
+! *** check whether evaluating f(x0 + step) looks worthwhile ***
+!
+ if (v(dstnrm) .le. zero) go to 180
+ if (iv(irc) .ne. 5) go to 170
+ if (v(radfac) .le. one) go to 170
+ if (v(preduc) .le. onep2 * v(fdif)) go to 180
+!
+! *** compute f(x0 + step) ***
+!
+ 170 x01 = iv(x0)
+ step1 = iv(step)
+ call vaxpy(n, x, one, v(step1), v(x01))
+ iv(nfcall) = iv(nfcall) + 1
+ iv(1) = 1
+ iv(toobig) = 0
+ go to 999
+!
+!. . . . . . . . . . . . . assess candidate step . . . . . . . . . . .
+!
+ 180 x01 = iv(x0)
+ v(reldx) = reldst(n, d, x, v(x01))
+ call assst(iv, liv, lv, v)
+ step1 = iv(step)
+ lstgst = iv(stlstg)
+ if (iv(restor) .eq. 1) call vcopy(n, x, v(x01))
+ if (iv(restor) .eq. 2) call vcopy(n, v(lstgst), v(step1))
+ if (iv(restor) .ne. 3) go to 190
+ call vcopy(n, v(step1), v(lstgst))
+ call vaxpy(n, x, one, v(step1), v(x01))
+ v(reldx) = reldst(n, d, x, v(x01))
+!
+ 190 k = iv(irc)
+ go to (200,230,230,230,200,210,220,220,220,220,220,220,280,250), k
+!
+! *** recompute step with changed radius ***
+!
+ 200 v(radius) = v(radfac) * v(dstnrm)
+ go to 110
+!
+! *** compute step of length v(lmaxs) for singular convergence test.
+!
+ 210 v(radius) = v(lmaxs)
+ go to 150
+!
+! *** convergence or false convergence ***
+!
+ 220 iv(cnvcod) = k - 4
+ if (v(f) .ge. v(f0)) go to 290
+ if (iv(xirc) .eq. 14) go to 290
+ iv(xirc) = 14
+!
+!. . . . . . . . . . . . process acceptable step . . . . . . . . . . .
+!
+ 230 if (iv(irc) .ne. 3) go to 240
+ step1 = iv(step)
+ temp1 = iv(stlstg)
+!
+! *** set temp1 = hessian * step for use in gradient tests ***
+!
+ l = iv(lmat)
+ call ltvmul(n, v(temp1), v(l), v(step1))
+ call lvmul(n, v(temp1), v(l), v(temp1))
+!
+! *** compute gradient ***
+!
+ 240 iv(ngcall) = iv(ngcall) + 1
+ iv(1) = 2
+ go to 999
+!
+! *** initializations -- g0 = g - g0, etc. ***
+!
+ 250 g01 = iv(g0)
+ call vaxpy(n, v(g01), negone, v(g01), g)
+ step1 = iv(step)
+ temp1 = iv(stlstg)
+ if (iv(irc) .ne. 3) go to 270
+!
+! *** set v(radfac) by gradient tests ***
+!
+! *** set temp1 = diag(d)**-1 * (hessian*step + (g(x0)-g(x))) ***
+!
+ call vaxpy(n, v(temp1), negone, v(g01), v(temp1))
+ call vvmulp(n, v(temp1), v(temp1), d, -1)
+!
+! *** do gradient tests ***
+!
+ if (v2norm(n, v(temp1)) .le. v(dgnorm) * v(tuner4)) &
+ go to 260
+ if (dotprd(n, g, v(step1)) &
+ .ge. v(gtstep) * v(tuner5)) go to 270
+ 260 v(radfac) = v(incfac)
+!
+! *** update h, loop ***
+!
+ 270 w = iv(nwtstp)
+ z = iv(x0)
+ l = iv(lmat)
+ call wzbfgs(v(l), n, v(step1), v(w), v(g01), v(z))
+!
+! ** use the n-vectors starting at v(step1) and v(g01) for scratch..
+ call lupdat(v(temp1), v(step1), v(l), v(g01), v(l), n, v(w), v(z))
+ iv(1) = 2
+ go to 80
+!
+!. . . . . . . . . . . . . . misc. details . . . . . . . . . . . . . .
+!
+! *** bad parameters to assess ***
+!
+ 280 iv(1) = 64
+ go to 300
+!
+! *** print summary of final iteration and other requested items ***
+!
+ 290 iv(1) = iv(cnvcod)
+ iv(cnvcod) = 0
+ 300 call itsum(d, g, iv, liv, lv, n, v, x)
+!
+ 999 return
+!
+! *** last line of sumit follows ***
+ end subroutine sumit
+!-----------------------------------------------------------------------------
+ subroutine dbdog(dig,lv,n,nwtstp,step,v)
+!
+! *** compute double dogleg step ***
+!
+! *** parameter declarations ***
+!
+ integer :: lv, n
+ real(kind=8) :: dig(n), nwtstp(n), step(n), v(lv)
+!
+! *** purpose ***
+!
+! this subroutine computes a candidate step (for use in an uncon-
+! strained minimization code) by the double dogleg algorithm of
+! dennis and mei (ref. 1), which is a variation on powell*s dogleg
+! scheme (ref. 2, p. 95).
+!
+!-------------------------- parameter usage --------------------------
+!
+! dig (input) diag(d)**-2 * g -- see algorithm notes.
+! g (input) the current gradient vector.
+! lv (input) length of v.
+! n (input) number of components in dig, g, nwtstp, and step.
+! nwtstp (input) negative newton step -- see algorithm notes.
+! step (output) the computed step.
+! v (i/o) values array, the following components of which are
+! used here...
+! v(bias) (input) bias for relaxed newton step, which is v(bias) of
+! the way from the full newton to the fully relaxed newton
+! step. recommended value = 0.8 .
+! v(dgnorm) (input) 2-norm of diag(d)**-1 * g -- see algorithm notes.
+! v(dstnrm) (output) 2-norm of diag(d) * step, which is v(radius)
+! unless v(stppar) = 0 -- see algorithm notes.
+! v(dst0) (input) 2-norm of diag(d) * nwtstp -- see algorithm notes.
+! v(grdfac) (output) the coefficient of dig in the step returned --
+! step(i) = v(grdfac)*dig(i) + v(nwtfac)*nwtstp(i).
+! v(gthg) (input) square-root of (dig**t) * (hessian) * dig -- see
+! algorithm notes.
+! v(gtstep) (output) inner product between g and step.
+! v(nreduc) (output) function reduction predicted for the full newton
+! step.
+! v(nwtfac) (output) the coefficient of nwtstp in the step returned --
+! see v(grdfac) above.
+! v(preduc) (output) function reduction predicted for the step returned.
+! v(radius) (input) the trust region radius. d times the step returned
+! has 2-norm v(radius) unless v(stppar) = 0.
+! v(stppar) (output) code telling how step was computed... 0 means a
+! full newton step. between 0 and 1 means v(stppar) of the
+! way from the newton to the relaxed newton step. between
+! 1 and 2 means a true double dogleg step, v(stppar) - 1 of
+! the way from the relaxed newton to the cauchy step.
+! greater than 2 means 1 / (v(stppar) - 1) times the cauchy
+! step.
+!
+!------------------------------- notes -------------------------------
+!
+! *** algorithm notes ***
+!
+! let g and h be the current gradient and hessian approxima-
+! tion respectively and let d be the current scale vector. this
+! routine assumes dig = diag(d)**-2 * g and nwtstp = h**-1 * g.
+! the step computed is the same one would get by replacing g and h
+! by diag(d)**-1 * g and diag(d)**-1 * h * diag(d)**-1,
+! computing step, and translating step back to the original
+! variables, i.e., premultiplying it by diag(d)**-1.
+!
+! *** references ***
+!
+! 1. dennis, j.e., and mei, h.h.w. (1979), two new unconstrained opti-
+! mization algorithms which use function and gradient
+! values, j. optim. theory applic. 28, pp. 453-482.
+! 2. powell, m.j.d. (1970), a hybrid method for non-linear equations,
+! in numerical methods for non-linear equations, edited by
+! p. rabinowitz, gordon and breach, london.
+!
+! *** general ***
+!
+! coded by david m. gay.
+! this subroutine was written in connection with research supported
+! by the national science foundation under grants mcs-7600324 and
+! mcs-7906671.
+!
+!------------------------ external quantities ------------------------
+!
+! *** functions and subroutines called ***
+!
+!el external dotprd, v2norm
+!el real(kind=8) :: dotprd, v2norm
+!
+! dotprd... returns inner product of two vectors.
+! v2norm... returns 2-norm of a vector.
+!
+! *** intrinsic functions ***
+!/+
+!el real(kind=8) :: dsqrt
+!/
+!-------------------------- local variables --------------------------
+!
+ integer :: i
+ real(kind=8) :: cfact, cnorm, ctrnwt, ghinvg, femnsq, gnorm,&
+ nwtnrm, relax, rlambd, t, t1, t2
+!el real(kind=8) :: half, one, two, zero
+!
+! *** v subscripts ***
+!
+!el integer bias, dgnorm, dstnrm, dst0, grdfac, gthg, gtstep,
+!el 1 nreduc, nwtfac, preduc, radius, stppar
+!
+! *** data initializations ***
+!
+!/6
+! data half/0.5d+0/, one/1.d+0/, two/2.d+0/, zero/0.d+0/
+!/7
+ real(kind=8),parameter :: half=0.5d+0, one=1.d+0, two=2.d+0, zero=0.d+0
+!/
+!
+!/6
+! data bias/43/, dgnorm/1/, dstnrm/2/, dst0/3/, grdfac/45/,
+! 1 gthg/44/, gtstep/4/, nreduc/6/, nwtfac/46/, preduc/7/,
+! 2 radius/8/, stppar/5/
+!/7
+ integer,parameter :: bias=43, dgnorm=1, dstnrm=2, dst0=3, grdfac=45,&
+ gthg=44, gtstep=4, nreduc=6, nwtfac=46, preduc=7,&
+ radius=8, stppar=5
+!/
+!
+!+++++++++++++++++++++++++++++++ body ++++++++++++++++++++++++++++++++
+!
+ nwtnrm = v(dst0)
+ rlambd = one
+ if (nwtnrm .gt. zero) rlambd = v(radius) / nwtnrm
+ gnorm = v(dgnorm)
+ ghinvg = two * v(nreduc)
+ v(grdfac) = zero
+ v(nwtfac) = zero
+ if (rlambd .lt. one) go to 30
+!
+! *** the newton step is inside the trust region ***
+!
+ v(stppar) = zero
+ v(dstnrm) = nwtnrm
+ v(gtstep) = -ghinvg
+ v(preduc) = v(nreduc)
+ v(nwtfac) = -one
+ do 20 i = 1, n
+ 20 step(i) = -nwtstp(i)
+ go to 999
+!
+ 30 v(dstnrm) = v(radius)
+ cfact = (gnorm / v(gthg))**2
+! *** cauchy step = -cfact * g.
+ cnorm = gnorm * cfact
+ relax = one - v(bias) * (one - gnorm*cnorm/ghinvg)
+ if (rlambd .lt. relax) go to 50
+!
+! *** step is between relaxed newton and full newton steps ***
+!
+ v(stppar) = one - (rlambd - relax) / (one - relax)
+ t = -rlambd
+ v(gtstep) = t * ghinvg
+ v(preduc) = rlambd * (one - half*rlambd) * ghinvg
+ v(nwtfac) = t
+ do 40 i = 1, n
+ 40 step(i) = t * nwtstp(i)
+ go to 999
+!
+ 50 if (cnorm .lt. v(radius)) go to 70
+!
+! *** the cauchy step lies outside the trust region --
+! *** step = scaled cauchy step ***
+!
+ t = -v(radius) / gnorm
+ v(grdfac) = t
+ v(stppar) = one + cnorm / v(radius)
+ v(gtstep) = -v(radius) * gnorm
+ v(preduc) = v(radius)*(gnorm - half*v(radius)*(v(gthg)/gnorm)**2)
+ do 60 i = 1, n
+ 60 step(i) = t * dig(i)
+ go to 999
+!
+! *** compute dogleg step between cauchy and relaxed newton ***
+! *** femur = relaxed newton step minus cauchy step ***
+!
+ 70 ctrnwt = cfact * relax * ghinvg / gnorm
+! *** ctrnwt = inner prod. of cauchy and relaxed newton steps,
+! *** scaled by gnorm**-1.
+ t1 = ctrnwt - gnorm*cfact**2
+! *** t1 = inner prod. of femur and cauchy step, scaled by
+! *** gnorm**-1.
+ t2 = v(radius)*(v(radius)/gnorm) - gnorm*cfact**2
+ t = relax * nwtnrm
+ femnsq = (t/gnorm)*t - ctrnwt - t1
+! *** femnsq = square of 2-norm of femur, scaled by gnorm**-1.
+ t = t2 / (t1 + dsqrt(t1**2 + femnsq*t2))
+! *** dogleg step = cauchy step + t * femur.
+ t1 = (t - one) * cfact
+ v(grdfac) = t1
+ t2 = -t * relax
+ v(nwtfac) = t2
+ v(stppar) = two - t
+ v(gtstep) = t1*gnorm**2 + t2*ghinvg
+ v(preduc) = -t1*gnorm * ((t2 + one)*gnorm) &
+ - t2 * (one + half*t2)*ghinvg &
+ - half * (v(gthg)*t1)**2
+ do 80 i = 1, n
+ 80 step(i) = t1*dig(i) + t2*nwtstp(i)
+!
+ 999 return
+! *** last line of dbdog follows ***
+ end subroutine dbdog
+!-----------------------------------------------------------------------------
+ subroutine ltvmul(n,x,l,y)
+!
+! *** compute x = (l**t)*y, where l is an n x n lower
+! *** triangular matrix stored compactly by rows. x and y may
+! *** occupy the same storage. ***
+!
+ integer :: n
+!al real(kind=8) :: x(n), l(1), y(n)
+ real(kind=8) :: x(n), l(n*(n+1)/2), y(n)
+! dimension l(n*(n+1)/2)
+ integer :: i, ij, i0, j
+ real(kind=8) :: yi !el, zero
+!/6
+! data zero/0.d+0/
+!/7
+ real(kind=8),parameter :: zero=0.d+0
+!/
+!
+ i0 = 0
+ do 20 i = 1, n
+ yi = y(i)
+ x(i) = zero
+ do 10 j = 1, i
+ ij = i0 + j
+ x(j) = x(j) + yi*l(ij)
+ 10 continue
+ i0 = i0 + i
+ 20 continue
+ 999 return
+! *** last card of ltvmul follows ***
+ end subroutine ltvmul
+!-----------------------------------------------------------------------------
+ subroutine lupdat(beta,gamma,l,lambda,lplus,n,w,z)
+!
+! *** compute lplus = secant update of l ***
+!
+! *** parameter declarations ***
+!
+ integer :: n
+!al double precision beta(n), gamma(n), l(1), lambda(n), lplus(1),
+ real(kind=8) :: beta(n), gamma(n), l(n*(n+1)/2), lambda(n), &
+ lplus(n*(n+1)/2),w(n), z(n)
+! dimension l(n*(n+1)/2), lplus(n*(n+1)/2)
+!
+!-------------------------- parameter usage --------------------------
+!
+! beta = scratch vector.
+! gamma = scratch vector.
+! l (input) lower triangular matrix, stored rowwise.
+! lambda = scratch vector.
+! lplus (output) lower triangular matrix, stored rowwise, which may
+! occupy the same storage as l.
+! n (input) length of vector parameters and order of matrices.
+! w (input, destroyed on output) right singular vector of rank 1
+! correction to l.
+! z (input, destroyed on output) left singular vector of rank 1
+! correction to l.
+!
+!------------------------------- notes -------------------------------
+!
+! *** application and usage restrictions ***
+!
+! this routine updates the cholesky factor l of a symmetric
+! positive definite matrix to which a secant update is being
+! applied -- it computes a cholesky factor lplus of
+! l * (i + z*w**t) * (i + w*z**t) * l**t. it is assumed that w
+! and z have been chosen so that the updated matrix is strictly
+! positive definite.
+!
+! *** algorithm notes ***
+!
+! this code uses recurrence 3 of ref. 1 (with d(j) = 1 for all j)
+! to compute lplus of the form l * (i + z*w**t) * q, where q
+! is an orthogonal matrix that makes the result lower triangular.
+! lplus may have some negative diagonal elements.
+!
+! *** references ***
+!
+! 1. goldfarb, d. (1976), factorized variable metric methods for uncon-
+! strained optimization, math. comput. 30, pp. 796-811.
+!
+! *** general ***
+!
+! coded by david m. gay (fall 1979).
+! this subroutine was written in connection with research supported
+! by the national science foundation under grants mcs-7600324 and
+! mcs-7906671.
+!
+!------------------------ external quantities ------------------------
+!
+! *** intrinsic functions ***
+!/+
+!el real(kind=8) :: dsqrt
+!/
+!-------------------------- local variables --------------------------
+!
+ integer :: i, ij, j, jj, jp1, k, nm1, np1
+ real(kind=8) :: a, b, bj, eta, gj, lj, lij, ljj, nu, s, theta,&
+ wj, zj
+!el real(kind=8) :: one, zero
+!
+! *** data initializations ***
+!
+!/6
+! data one/1.d+0/, zero/0.d+0/
+!/7
+ real(kind=8),parameter :: one=1.d+0, zero=0.d+0
+!/
+!
+!+++++++++++++++++++++++++++++++ body ++++++++++++++++++++++++++++++++
+!
+ nu = one
+ eta = zero
+ if (n .le. 1) go to 30
+ nm1 = n - 1
+!
+! *** temporarily store s(j) = sum over k = j+1 to n of w(k)**2 in
+! *** lambda(j).
+!
+ s = zero
+ do 10 i = 1, nm1
+ j = n - i
+ s = s + w(j+1)**2
+ lambda(j) = s
+ 10 continue
+!
+! *** compute lambda, gamma, and beta by goldfarb*s recurrence 3.
+!
+ do 20 j = 1, nm1
+ wj = w(j)
+ a = nu*z(j) - eta*wj
+ theta = one + a*wj
+ s = a*lambda(j)
+ lj = dsqrt(theta**2 + a*s)
+ if (theta .gt. zero) lj = -lj
+ lambda(j) = lj
+ b = theta*wj + s
+ gamma(j) = b * nu / lj
+ beta(j) = (a - b*eta) / lj
+ nu = -nu / lj
+ eta = -(eta + (a**2)/(theta - lj)) / lj
+ 20 continue
+ 30 lambda(n) = one + (nu*z(n) - eta*w(n))*w(n)
+!
+! *** update l, gradually overwriting w and z with l*w and l*z.
+!
+ np1 = n + 1
+ jj = n * (n + 1) / 2
+ do 60 k = 1, n
+ j = np1 - k
+ lj = lambda(j)
+ ljj = l(jj)
+ lplus(jj) = lj * ljj
+ wj = w(j)
+ w(j) = ljj * wj
+ zj = z(j)
+ z(j) = ljj * zj
+ if (k .eq. 1) go to 50
+ bj = beta(j)
+ gj = gamma(j)
+ ij = jj + j
+ jp1 = j + 1
+ do 40 i = jp1, n
+ lij = l(ij)
+ lplus(ij) = lj*lij + bj*w(i) + gj*z(i)
+ w(i) = w(i) + lij*wj
+ z(i) = z(i) + lij*zj
+ ij = ij + i
+ 40 continue
+ 50 jj = jj - j
+ 60 continue
+!
+ 999 return
+! *** last card of lupdat follows ***
+ end subroutine lupdat
+!-----------------------------------------------------------------------------
+ subroutine lvmul(n,x,l,y)
+!
+! *** compute x = l*y, where l is an n x n lower triangular
+! *** matrix stored compactly by rows. x and y may occupy the same
+! *** storage. ***
+!
+ integer :: n
+!al double precision x(n), l(1), y(n)
+ real(kind=8) :: x(n), l(n*(n+1)/2), y(n)
+! dimension l(n*(n+1)/2)
+ integer :: i, ii, ij, i0, j, np1
+ real(kind=8) :: t !el, zero
+!/6
+! data zero/0.d+0/
+!/7
+ real(kind=8),parameter :: zero=0.d+0
+!/
+!
+ np1 = n + 1
+ i0 = n*(n+1)/2
+ do 20 ii = 1, n
+ i = np1 - ii
+ i0 = i0 - i
+ t = zero
+ do 10 j = 1, i
+ ij = i0 + j
+ t = t + l(ij)*y(j)
+ 10 continue
+ x(i) = t
+ 20 continue
+ 999 return
+! *** last card of lvmul follows ***
+ end subroutine lvmul
+!-----------------------------------------------------------------------------
+ subroutine vvmulp(n,x,y,z,k)
+!
+! *** set x(i) = y(i) * z(i)**k, 1 .le. i .le. n (for k = 1 or -1) ***
+!
+ integer :: n, k
+ real(kind=8) :: x(n), y(n), z(n)
+ integer :: i
+!
+ if (k .ge. 0) go to 20
+ do 10 i = 1, n
+ 10 x(i) = y(i) / z(i)
+ go to 999
+!
+ 20 do 30 i = 1, n
+ 30 x(i) = y(i) * z(i)
+ 999 return
+! *** last card of vvmulp follows ***
+ end subroutine vvmulp
+!-----------------------------------------------------------------------------
+ subroutine wzbfgs(l,n,s,w,y,z)
+!
+! *** compute y and z for lupdat corresponding to bfgs update.
+!
+ integer :: n
+!al double precision l(1), s(n), w(n), y(n), z(n)
+ real(kind=8) :: l(n*(n+1)/2), s(n), w(n), y(n), z(n)
+! dimension l(n*(n+1)/2)
+!
+!-------------------------- parameter usage --------------------------
+!
+! l (i/o) cholesky factor of hessian, a lower triang. matrix stored
+! compactly by rows.
+! n (input) order of l and length of s, w, y, z.
+! s (input) the step just taken.
+! w (output) right singular vector of rank 1 correction to l.
+! y (input) change in gradients corresponding to s.
+! z (output) left singular vector of rank 1 correction to l.
+!
+!------------------------------- notes -------------------------------
+!
+! *** algorithm notes ***
+!
+! when s is computed in certain ways, e.g. by gqtstp or
+! dbldog, it is possible to save n**2/2 operations since (l**t)*s
+! or l*(l**t)*s is then known.
+! if the bfgs update to l*(l**t) would reduce its determinant to
+! less than eps times its old value, then this routine in effect
+! replaces y by theta*y + (1 - theta)*l*(l**t)*s, where theta
+! (between 0 and 1) is chosen to make the reduction factor = eps.
+!
+! *** general ***
+!
+! coded by david m. gay (fall 1979).
+! this subroutine was written in connection with research supported
+! by the national science foundation under grants mcs-7600324 and
+! mcs-7906671.
+!
+!------------------------ external quantities ------------------------
+!
+! *** functions and subroutines called ***
+!
+!el external dotprd, livmul, ltvmul
+!el real(kind=8) :: dotprd
+! dotprd returns inner product of two vectors.
+! livmul multiplies l**-1 times a vector.
+! ltvmul multiplies l**t times a vector.
+!
+! *** intrinsic functions ***
+!/+
+!el real(kind=8) :: dsqrt
+!/
+!-------------------------- local variables --------------------------
+!
+ integer :: i
+ real(kind=8) :: cs, cy, epsrt, shs, ys, theta !el, eps, one
+!
+! *** data initializations ***
+!
+!/6
+! data eps/0.1d+0/, one/1.d+0/
+!/7
+ real(kind=8),parameter :: eps=0.1d+0, one=1.d+0
+!/
+!
+!+++++++++++++++++++++++++++++++ body ++++++++++++++++++++++++++++++++
+!
+ call ltvmul(n, w, l, s)
+ shs = dotprd(n, w, w)
+ ys = dotprd(n, y, s)
+ if (ys .ge. eps*shs) go to 10
+ theta = (one - eps) * shs / (shs - ys)
+ epsrt = dsqrt(eps)
+ cy = theta / (shs * epsrt)
+ cs = (one + (theta-one)/epsrt) / shs
+ go to 20
+ 10 cy = one / (dsqrt(ys) * dsqrt(shs))
+ cs = one / shs
+ 20 call livmul(n, z, l, y)
+ do 30 i = 1, n
+ 30 z(i) = cy * z(i) - cs * w(i)
+!
+ 999 return
+! *** last card of wzbfgs follows ***
+ end subroutine wzbfgs
+!-----------------------------------------------------------------------------
+!-----------------------------------------------------------------------------
+ end module minimm