source/unres/src_MD-M/chainbuild.F

   1       subroutine chainbuild
   2 C
   3 C Build the virtual polypeptide chain. Side-chain centroids are moveable.
   4 C As of 2/17/95.
   5 C
   6       implicit real*8 (a-h,o-z)
   7       include 'DIMENSIONS'
   8       include 'COMMON.CHAIN'
   9       include 'COMMON.LOCAL'
  10       include 'COMMON.GEO'
  11       include 'COMMON.VAR'
  12       include 'COMMON.IOUNITS'
  13       include 'COMMON.NAMES'
  14       include 'COMMON.INTERACT'
  15       double precision e1(3),e2(3),e3(3)
  16       logical lprn,perbox,fail
  17 C Set lprn=.true. for debugging
  18       lprn = .false.
  19       perbox=.false.
  20       fail=.false.
  21       print *, 'enter chainbuild'
  22       if (perbox) then
  23       cost=dcos(theta(3))
  24       sint=dsin(theta(3))
  25       print *,'before refsys'
  26       call refsys(2,3,4,e1,e2,e3,fail)
  27       print *,'after refsys'
  28           if (fail) then
  29             e2(1)=0.0d0
  30             e2(2)=1.0d0
  31             e2(3)=0.0d0
  32           endif
  33       dc(1,0)=c(1,1)
  34       dc(2,0)=c(2,1)
  35       dc(3,0)=c(3,1)
  36       print *,'dc',dc(1,0),dc(2,0),dc(3,0)
  37       dc(1,1)=c(1,2)-c(1,1)
  38       dc(2,1)=c(2,2)-c(2,1)
  39       dc(3,1)=c(3,2)-c(3,1)
  40       dc(1,2)=c(1,3)-c(1,2)
  41       dc(2,2)=c(2,3)-c(2,2)
  42       dc(3,2)=c(3,3)-c(3,2)
  43       t(1,1,1)=e1(1)
  44       t(1,2,1)=e1(2)
  45       t(1,3,1)=e1(3)
  46       t(2,1,1)=e2(1)
  47       t(2,2,1)=e2(2)
  48       t(2,3,1)=e2(3)
  49       t(3,1,1)=e3(1)
  50       t(3,2,1)=e3(2)
  51       t(3,3,1)=e3(3)
  52       veclen=0.0d0
  53       do i=1,3
  54        veclen=veclen+(c(i,2)-c(i,1))**2
  55       enddo
  56       veclen=sqrt(veclen)
  57       r(1,1,1)= 1.0D0
  58       r(1,2,1)= 0.0D0
  59       r(1,3,1)= 0.0D0
  60       r(2,1,1)= 0.0D0
  61       r(2,2,1)= 1.0D0
  62       r(2,3,1)= 0.0D0
  63       r(3,1,1)= 0.0D0
  64       r(3,2,1)= 0.0D0
  65       r(3,3,1)= 1.0D0
  66       do i=1,3
  67         do j=1,3
  68           rt(i,j,1)=t(i,j,1)
  69         enddo
  70       enddo
  71       do i=1,3
  72         do j=1,3
  73           prod(i,j,1)=0.0D0
  74           prod(i,j,2)=t(i,j,1)
  75         enddo
  76         prod(i,i,1)=1.0D0
  77       enddo
  78         call locate_side_chain(2)
  79       do i=4,nres
  80 #ifdef OSF
  81       theti=theta(i)
  82       if (theti.ne.theti) theti=100.0
  83       phii=phi(i)
  84       if (phii.ne.phii) phii=180.0
  85 #else
  86       theti=theta(i)
  87       phii=phi(i)
  88 #endif
  89       cost=dcos(theti)
  90       sint=dsin(theti)
  91       cosphi=dcos(phii)
  92       sinphi=dsin(phii)
  93 * Define the matrices of the rotation about the virtual-bond valence angles
  94 * theta, T(i,j,k), virtual-bond dihedral angles gamma (miscalled PHI in this
  95 * program), R(i,j,k), and, the cumulative matrices of rotation RT
  96       t(1,1,i-2)=-cost
  97       t(1,2,i-2)=-sint
  98       t(1,3,i-2)= 0.0D0
  99       t(2,1,i-2)=-sint
 100       t(2,2,i-2)= cost
 101       t(2,3,i-2)= 0.0D0
 102       t(3,1,i-2)= 0.0D0
 103       t(3,2,i-2)= 0.0D0
 104       t(3,3,i-2)= 1.0D0
 105       r(1,1,i-2)= 1.0D0
 106       r(1,2,i-2)= 0.0D0
 107       r(1,3,i-2)= 0.0D0
 108       r(2,1,i-2)= 0.0D0
 109       r(2,2,i-2)=-cosphi
 110       r(2,3,i-2)= sinphi
 111       r(3,1,i-2)= 0.0D0
 112       r(3,2,i-2)= sinphi
 113       r(3,3,i-2)= cosphi
 114       rt(1,1,i-2)=-cost
 115       rt(1,2,i-2)=-sint
 116       rt(1,3,i-2)=0.0D0
 117       rt(2,1,i-2)=sint*cosphi
 118       rt(2,2,i-2)=-cost*cosphi
 119       rt(2,3,i-2)=sinphi
 120       rt(3,1,i-2)=-sint*sinphi
 121       rt(3,2,i-2)=cost*sinphi
 122       rt(3,3,i-2)=cosphi
 123         call matmult(prod(1,1,i-2),rt(1,1,i-2),prod(1,1,i-1))
 124       do j=1,3
 125         dc_norm(j,i-1)=prod(j,1,i-1)
 126         dc(j,i-1)=vbld(i)*prod(j,1,i-1)
 127       enddo
 128         call locate_side_chain(i-1)
 129        enddo
 130       else
 131 C
 132 C Define the origin and orientation of the coordinate system and locate the
 133 C first three CA's and SC(2).
 134 C
 135       call orig_frame
 136 *
 137 * Build the alpha-carbon chain.
 138 *
 139       do i=4,nres
 140         call locate_next_res(i)
 141       enddo
 142 C
 143 C First and last SC must coincide with the corresponding CA.
 144 C
 145       do j=1,3
 146         dc(j,nres+1)=0.0D0
 147         dc_norm(j,nres+1)=0.0D0
 148         dc(j,nres+nres)=0.0D0
 149         dc_norm(j,nres+nres)=0.0D0
 150         c(j,nres+1)=c(j,1)
 151         c(j,nres+nres)=c(j,nres)
 152       enddo
 153 *
 154 * Temporary diagnosis
 155 *
 156       if (lprn) then
 157
 158       call cartprint
 159       write (iout,'(/a)') 'Recalculated internal coordinates'
 160       do i=2,nres-1
 161         do j=1,3
 162           c(j,maxres2)=0.5D0*(c(j,i-1)+c(j,i+1))
 163         enddo
 164         be=0.0D0
 165         if (i.gt.3) be=rad2deg*beta(i-3,i-2,i-1,i)
 166         be1=rad2deg*beta(nres+i,i,maxres2,i+1)
 167         alfai=0.0D0
 168         if (i.gt.2) alfai=rad2deg*alpha(i-2,i-1,i)
 169         write (iout,1212) restyp(itype(i)),i,dist(i-1,i),
 170      &  alfai,be,dist(nres+i,i),rad2deg*alpha(nres+i,i,maxres2),be1
 171       enddo
 172  1212 format (a3,'(',i3,')',2(f10.5,2f10.2))
 173
 174       endif
 175       endif
 176       return
 177       end
 178 c-------------------------------------------------------------------------
 179       subroutine orig_frame
 180 C
 181 C Define the origin and orientation of the coordinate system and locate
 182 C the first three atoms.
 183 C
 184       implicit real*8 (a-h,o-z)
 185       include 'DIMENSIONS'
 186       include 'COMMON.CHAIN'
 187       include 'COMMON.LOCAL'
 188       include 'COMMON.GEO'
 189       include 'COMMON.VAR'
 190       cost=dcos(theta(3))
 191       sint=dsin(theta(3))
 192       t(1,1,1)=-cost
 193       t(1,2,1)=-sint
 194       t(1,3,1)= 0.0D0
 195       t(2,1,1)=-sint
 196       t(2,2,1)= cost
 197       t(2,3,1)= 0.0D0
 198       t(3,1,1)= 0.0D0
 199       t(3,2,1)= 0.0D0
 200       t(3,3,1)= 1.0D0
 201       r(1,1,1)= 1.0D0
 202       r(1,2,1)= 0.0D0
 203       r(1,3,1)= 0.0D0
 204       r(2,1,1)= 0.0D0
 205       r(2,2,1)= 1.0D0
 206       r(2,3,1)= 0.0D0
 207       r(3,1,1)= 0.0D0
 208       r(3,2,1)= 0.0D0
 209       r(3,3,1)= 1.0D0
 210       do i=1,3
 211         do j=1,3
 212           rt(i,j,1)=t(i,j,1)
 213         enddo
 214       enddo
 215       do i=1,3
 216         do j=1,3
 217           prod(i,j,1)=0.0D0
 218           prod(i,j,2)=t(i,j,1)
 219         enddo
 220         prod(i,i,1)=1.0D0
 221       enddo
 222       c(1,1)=0.0D0
 223       c(2,1)=0.0D0
 224       c(3,1)=0.0D0
 225       c(1,2)=vbld(2)
 226       c(2,2)=0.0D0
 227       c(3,2)=0.0D0
 228       dc(1,0)=0.0d0
 229       dc(2,0)=0.0D0
 230       dc(3,0)=0.0D0
 231       dc(1,1)=vbld(2)
 232       dc(2,1)=0.0D0
 233       dc(3,1)=0.0D0
 234       dc_norm(1,0)=0.0D0
 235       dc_norm(2,0)=0.0D0
 236       dc_norm(3,0)=0.0D0
 237       dc_norm(1,1)=1.0D0
 238       dc_norm(2,1)=0.0D0
 239       dc_norm(3,1)=0.0D0
 240       do j=1,3
 241         dc_norm(j,2)=prod(j,1,2)
 242         dc(j,2)=vbld(3)*prod(j,1,2)
 243         c(j,3)=c(j,2)+dc(j,2)
 244       enddo
 245       call locate_side_chain(2)
 246       return
 247       end
 248 c-----------------------------------------------------------------------------
 249       subroutine locate_next_res(i)
 250 C
 251 C Locate CA(i) and SC(i-1)
 252 C
 253       implicit real*8 (a-h,o-z)
 254       include 'DIMENSIONS'
 255       include 'COMMON.CHAIN'
 256       include 'COMMON.LOCAL'
 257       include 'COMMON.GEO'
 258       include 'COMMON.VAR'
 259       include 'COMMON.IOUNITS'
 260       include 'COMMON.NAMES'
 261       include 'COMMON.INTERACT'
 262 C
 263 C Define the rotation matrices corresponding to CA(i)
 264 C
 265 #ifdef OSF
 266       theti=theta(i)
 267       if (theti.ne.theti) theti=100.0
 268       phii=phi(i)
 269       if (phii.ne.phii) phii=180.0
 270 #else
 271       theti=theta(i)
 272       phii=phi(i)
 273 #endif
 274       cost=dcos(theti)
 275       sint=dsin(theti)
 276       cosphi=dcos(phii)
 277       sinphi=dsin(phii)
 278 * Define the matrices of the rotation about the virtual-bond valence angles
 279 * theta, T(i,j,k), virtual-bond dihedral angles gamma (miscalled PHI in this
 280 * program), R(i,j,k), and, the cumulative matrices of rotation RT
 281       t(1,1,i-2)=-cost
 282       t(1,2,i-2)=-sint
 283       t(1,3,i-2)= 0.0D0
 284       t(2,1,i-2)=-sint
 285       t(2,2,i-2)= cost
 286       t(2,3,i-2)= 0.0D0
 287       t(3,1,i-2)= 0.0D0
 288       t(3,2,i-2)= 0.0D0
 289       t(3,3,i-2)= 1.0D0
 290       r(1,1,i-2)= 1.0D0
 291       r(1,2,i-2)= 0.0D0
 292       r(1,3,i-2)= 0.0D0
 293       r(2,1,i-2)= 0.0D0
 294       r(2,2,i-2)=-cosphi
 295       r(2,3,i-2)= sinphi
 296       r(3,1,i-2)= 0.0D0
 297       r(3,2,i-2)= sinphi
 298       r(3,3,i-2)= cosphi
 299       rt(1,1,i-2)=-cost
 300       rt(1,2,i-2)=-sint
 301       rt(1,3,i-2)=0.0D0
 302       rt(2,1,i-2)=sint*cosphi
 303       rt(2,2,i-2)=-cost*cosphi
 304       rt(2,3,i-2)=sinphi
 305       rt(3,1,i-2)=-sint*sinphi
 306       rt(3,2,i-2)=cost*sinphi
 307       rt(3,3,i-2)=cosphi
 308       call matmult(prod(1,1,i-2),rt(1,1,i-2),prod(1,1,i-1))
 309       do j=1,3
 310         dc_norm(j,i-1)=prod(j,1,i-1)
 311         dc(j,i-1)=vbld(i)*prod(j,1,i-1)
 312         c(j,i)=c(j,i-1)+dc(j,i-1)
 313       enddo
 314 cd    print '(2i3,2(3f10.5,5x))', i-1,i,(dc(j,i-1),j=1,3),(c(j,i),j=1,3)
 315 C
 316 C Now calculate the coordinates of SC(i-1)
 317 C
 318       call locate_side_chain(i-1)
 319       return
 320       end
 321 c-----------------------------------------------------------------------------
 322       subroutine locate_side_chain(i)
 323 C
 324 C Locate the side-chain centroid i, 1 < i < NRES. Put in C(*,NRES+i).
 325 C
 326       implicit real*8 (a-h,o-z)
 327       include 'DIMENSIONS'
 328       include 'COMMON.CHAIN'
 329       include 'COMMON.LOCAL'
 330       include 'COMMON.GEO'
 331       include 'COMMON.VAR'
 332       include 'COMMON.IOUNITS'
 333       include 'COMMON.NAMES'
 334       include 'COMMON.INTERACT'
 335       dimension xx(3)
 336
 337 c      dsci=dsc(itype(i))
 338 c      dsci_inv=dsc_inv(itype(i))
 339       dsci=vbld(i+nres)
 340       dsci_inv=vbld_inv(i+nres)
 341 #ifdef OSF
 342       alphi=alph(i)
 343       omegi=omeg(i)
 344       if (alphi.ne.alphi) alphi=100.0
 345       if (omegi.ne.omegi) omegi=-100.0
 346 #else
 347       alphi=alph(i)
 348       omegi=omeg(i)
 349 #endif
 350       cosalphi=dcos(alphi)
 351       sinalphi=dsin(alphi)
 352       cosomegi=dcos(omegi)
 353       sinomegi=dsin(omegi)
 354       xp= dsci*cosalphi
 355       yp= dsci*sinalphi*cosomegi
 356       zp=-dsci*sinalphi*sinomegi
 357 * Now we have to rotate the coordinate system by 180-theta(i)/2 so as to get its
 358 * X-axis aligned with the vector DC(*,i)
 359       theta2=pi-0.5D0*theta(i+1)
 360       cost2=dcos(theta2)
 361       sint2=dsin(theta2)
 362       xx(1)= xp*cost2+yp*sint2
 363       xx(2)=-xp*sint2+yp*cost2
 364       xx(3)= zp
 365 cd    print '(a3,i3,3f10.5,5x,3f10.5)',restyp(itype(i)),i,
 366 cd   &   xp,yp,zp,(xx(k),k=1,3)
 367       do j=1,3
 368         xloc(j,i)=xx(j)
 369       enddo
 370 * Bring the SC vectors to the common coordinate system.
 371       xx(1)=xloc(1,i)
 372       xx(2)=xloc(2,i)*r(2,2,i-1)+xloc(3,i)*r(2,3,i-1)
 373       xx(3)=xloc(2,i)*r(3,2,i-1)+xloc(3,i)*r(3,3,i-1)
 374       do j=1,3
 375         xrot(j,i)=xx(j)
 376       enddo
 377       do j=1,3
 378         rj=0.0D0
 379         do k=1,3
 380           rj=rj+prod(j,k,i-1)*xx(k)
 381         enddo
 382         dc(j,nres+i)=rj
 383         dc_norm(j,nres+i)=rj*dsci_inv
 384         c(j,nres+i)=c(j,i)+rj
 385       enddo
 386       return
 387       end
 388 c------------------------------------------
 389       subroutine returnbox
 390       include 'DIMENSIONS'
 391 #ifdef MPI
 392       include 'mpif.h'
 393 #endif
 394       include 'COMMON.CONTROL'
 395       include 'COMMON.VAR'
 396       include 'COMMON.MD'
 397 #ifndef LANG0
 398       include 'COMMON.LANGEVIN'
 399 #else
 400       include 'COMMON.LANGEVIN.lang0'
 401 #endif
 402       include 'COMMON.CHAIN'
 403       include 'COMMON.DERIV'
 404       include 'COMMON.GEO'
 405       include 'COMMON.LOCAL'
 406       include 'COMMON.INTERACT'
 407       include 'COMMON.IOUNITS'
 408       include 'COMMON.NAMES'
 409       include 'COMMON.TIME1'
 410       include 'COMMON.REMD'
 411       include 'COMMON.SETUP'
 412       include 'COMMON.MUCA'
 413       include 'COMMON.HAIRPIN'
 414 C change suggested by Ana - begin
 415       integer allareout
 416 C change suggested by Ana - end
 417         j=1
 418         chain_beg=1
 419 C        do i=1,nres
 420 C       write(*,*) 'initial', i,j,c(j,i)
 421 C        enddo
 422 C change suggested by Ana - begin
 423         allareout=1
 424 C change suggested by Ana -end
 425         do i=1,nres-1
 426          if ((itype(i).eq.ntyp1).and.(itype(i+1).eq.ntyp1)) then
 427           chain_end=i
 428           if (allareout.eq.1) then
 429             ireturnval=int(c(j,i)/boxxsize)
 430             if (c(j,i).le.0) ireturnval=ireturnval-1
 431             do k=chain_beg,chain_end
 432               c(j,k)=c(j,k)-ireturnval*boxxsize
 433               c(j,k+nres)=c(j,k+nres)-ireturnval*boxxsize
 434             enddo
 435 C Suggested by Ana
 436             if (chain_beg.eq.1)
 437      &      dc_old(1,0)=dc_old(1,0)-ireturnval*boxxsize
 438 C Suggested by Ana -end
 439            endif
 440            chain_beg=i+1
 441            allareout=1
 442          else
 443           if (int(c(j,i)/boxxsize).eq.0) allareout=0
 444          endif
 445         enddo
 446          if (allareout.eq.1) then
 447             ireturnval=int(c(j,i)/boxxsize)
 448             if (c(j,i).le.0) ireturnval=ireturnval-1
 449             do k=chain_beg,nres
 450               c(j,k)=c(j,k)-ireturnval*boxxsize
 451               c(j,k+nres)=c(j,k+nres)-ireturnval*boxxsize
 452             enddo
 453           endif
 454 C NO JUMP
 455 C        do i=1,nres
 456 C        write(*,*) 'befor no jump', i,j,c(j,i)
 457 C        enddo
 458         nojumpval=0
 459         do i=2,nres
 460            if (itype(i).eq.ntyp1 .and. itype(i-1).eq.ntyp1) then
 461              difference=abs(c(j,i-1)-c(j,i))
 462 C             print *,'diff', difference
 463              if (difference.gt.boxxsize/2.0) then
 464                 if (c(j,i-1).gt.c(j,i)) then
 465                   nojumpval=1
 466                  else
 467                    nojumpval=-1
 468                  endif
 469               else
 470               nojumpval=0
 471               endif
 472               endif
 473               c(j,i)=c(j,i)+nojumpval*boxxsize
 474               c(j,i+nres)=c(j,i+nres)+nojumpval*boxxsize
 475          enddo
 476        nojumpval=0
 477         do i=2,nres
 478            if (itype(i).eq.ntyp1 .and. itype(i-1).eq.ntyp1) then
 479              difference=abs(c(j,i-1)-c(j,i))
 480              if (difference.gt.boxxsize/2.0) then
 481                 if (c(j,i-1).gt.c(j,i)) then
 482                   nojumpval=1
 483                  else
 484                    nojumpval=-1
 485                  endif
 486               else
 487               nojumpval=0
 488               endif
 489              endif
 490               c(j,i)=c(j,i)+nojumpval*boxxsize
 491               c(j,i+nres)=c(j,i+nres)+nojumpval*boxxsize
 492          enddo
 493
 494 C        do i=1,nres
 495 C        write(*,*) 'after no jump', i,j,c(j,i)
 496 C        enddo
 497
 498 C NOW Y dimension
 499 C suggesed by Ana begins
 500         allareout=1
 501 C suggested by Ana ends
 502         j=2
 503         chain_beg=1
 504         do i=1,nres-1
 505          if ((itype(i).eq.ntyp1).and.(itype(i+1).eq.ntyp1)) then
 506           chain_end=i
 507           if (allareout.eq.1) then
 508             ireturnval=int(c(j,i)/boxysize)
 509             if (c(j,i).le.0) ireturnval=ireturnval-1
 510             do k=chain_beg,chain_end
 511               c(j,k)=c(j,k)-ireturnval*boxysize
 512              c(j,k+nres)=c(j,k+nres)-ireturnval*boxysize
 513             enddo
 514 C Suggested by Ana
 515             if (chain_beg.eq.1)
 516      &      dc_old(1,0)=dc_old(1,0)-ireturnval*boxxsize
 517 C Suggested by Ana -end
 518            endif
 519            chain_beg=i+1
 520            allareout=1
 521          else
 522           if (int(c(j,i)/boxysize).eq.0) allareout=0
 523          endif
 524         enddo
 525          if (allareout.eq.1) then
 526             ireturnval=int(c(j,i)/boxysize)
 527             if (c(j,i).le.0) ireturnval=ireturnval-1
 528             do k=chain_beg,nres
 529               c(j,k)=c(j,k)-ireturnval*boxysize
 530               c(j,k+nres)=c(j,k+nres)-ireturnval*boxysize
 531             enddo
 532           endif
 533         nojumpval=0
 534         do i=2,nres
 535            if (itype(i).eq.ntyp1 .and. itype(i-1).eq.ntyp1) then
 536              difference=abs(c(j,i-1)-c(j,i))
 537              if (difference.gt.boxysize/2.0) then
 538                 if (c(j,i-1).gt.c(j,i)) then
 539                   nojumpval=1
 540                  else
 541                    nojumpval=-1
 542                  endif
 543              else
 544               nojumpval=0
 545               endif
 546            endif
 547               c(j,i)=c(j,i)+nojumpval*boxysize
 548               c(j,i+nres)=c(j,i+nres)+nojumpval*boxysize
 549          enddo
 550       nojumpval=0
 551         do i=2,nres
 552            if (itype(i).eq.ntyp1 .and. itype(i-1).eq.ntyp1) then
 553              difference=abs(c(j,i-1)-c(j,i))
 554              if (difference.gt.boxysize/2.0) then
 555                 if (c(j,i-1).gt.c(j,i)) then
 556                   nojumpval=1
 557                  else
 558                    nojumpval=-1
 559                  endif
 560               else
 561               nojumpval=0
 562               endif
 563             endif
 564               c(j,i)=c(j,i)+nojumpval*boxysize
 565               c(j,i+nres)=c(j,i+nres)+nojumpval*boxysize
 566          enddo
 567 C Now Z dimension
 568 C Suggested by Ana -begins
 569         allareout=1
 570 C Suggested by Ana -ends
 571        j=3
 572         chain_beg=1
 573         do i=1,nres-1
 574          if ((itype(i).eq.ntyp1).and.(itype(i+1).eq.ntyp1)) then
 575           chain_end=i
 576           if (allareout.eq.1) then
 577             ireturnval=int(c(j,i)/boxysize)
 578             if (c(j,i).le.0) ireturnval=ireturnval-1
 579             do k=chain_beg,chain_end
 580               c(j,k)=c(j,k)-ireturnval*boxzsize
 581               c(j,k+nres)=c(j,k+nres)-ireturnval*boxzsize
 582             enddo
 583 C Suggested by Ana
 584             if (chain_beg.eq.1)
 585      &      dc_old(1,0)=dc_old(1,0)-ireturnval*boxxsize
 586 C Suggested by Ana -end
 587            endif
 588            chain_beg=i+1
 589            allareout=1
 590          else
 591           if (int(c(j,i)/boxzsize).eq.0) allareout=0
 592          endif
 593         enddo
 594          if (allareout.eq.1) then
 595             ireturnval=int(c(j,i)/boxzsize)
 596             if (c(j,i).le.0) ireturnval=ireturnval-1
 597             do k=chain_beg,nres
 598               c(j,k)=c(j,k)-ireturnval*boxzsize
 599               c(j,k+nres)=c(j,k+nres)-ireturnval*boxzsize
 600             enddo
 601           endif
 602         nojumpval=0
 603         do i=2,nres
 604            if (itype(i).eq.ntyp1 .and. itype(i-1).eq.ntyp1) then
 605              difference=abs(c(j,i-1)-c(j,i))
 606              if (difference.gt.(boxzsize/2.0)) then
 607                 if (c(j,i-1).gt.c(j,i)) then
 608                   nojumpval=1
 609                  else
 610                    nojumpval=-1
 611                  endif
 612               else
 613               nojumpval=0
 614               endif
 615             endif
 616               c(j,i)=c(j,i)+nojumpval*boxzsize
 617               c(j,i+nres)=c(j,i+nres)+nojumpval*boxzsize
 618          enddo
 619        nojumpval=0
 620         do i=2,nres
 621            if (itype(i).eq.ntyp1 .and. itype(i-1).eq.ntyp1) then
 622              difference=abs(c(j,i-1)-c(j,i))
 623              if (difference.gt.boxzsize/2.0) then
 624                 if (c(j,i-1).gt.c(j,i)) then
 625                   nojumpval=1
 626                  else
 627                    nojumpval=-1
 628                  endif
 629               else
 630               nojumpval=0
 631               endif
 632             endif
 633              c(j,i)=c(j,i)+nojumpval*boxzsize
 634               c(j,i+nres)=c(j,i+nres)+nojumpval*boxzsize
 635          enddo
 636
 637         return
 638         end
 639