c algorithm 611, collected algorithms from acm. c algorithm appeared in acm-trans. math. software, vol.9, no. 4, c dec., 1983, p. 503-524. integer function imdcon(k) c integer k c c *** return integer machine-dependent constants *** c c *** k = 1 means return standard output unit number. *** c *** k = 2 means return alternate output unit number. *** c *** k = 3 means return input unit number. *** c (note -- k = 2, 3 are used only by test programs.) c c +++ port version follows... c external i1mach c integer i1mach c integer mdperm(3) c data mdperm(1)/2/, mdperm(2)/4/, mdperm(3)/1/ c imdcon = i1mach(mdperm(k)) c +++ end of port version +++ c c +++ non-port version follows... integer mdcon(3) data mdcon(1)/6/, mdcon(2)/8/, mdcon(3)/5/ imdcon = mdcon(k) c +++ end of non-port version +++ c 999 return c *** last card of imdcon follows *** end double precision function rmdcon(k) c c *** return machine dependent constants used by nl2sol *** c c +++ comments below contain data statements for various machines. +++ c +++ to convert to another machine, place a c in column 1 of the +++ c +++ data statement line(s) that correspond to the current machine +++ c +++ and remove the c from column 1 of the data statement line(s) +++ c +++ that correspond to the new machine. +++ c integer k c c *** the constant returned depends on k... c c *** k = 1... smallest pos. eta such that -eta exists. c *** k = 2... square root of eta. c *** k = 3... unit roundoff = smallest pos. no. machep such c *** that 1 + machep .gt. 1 .and. 1 - machep .lt. 1. c *** k = 4... square root of machep. c *** k = 5... square root of big (see k = 6). c *** k = 6... largest machine no. big such that -big exists. c double precision big, eta, machep integer bigi(4), etai(4), machei(4) c/+ double precision dsqrt c/ equivalence (big,bigi(1)), (eta,etai(1)), (machep,machei(1)) c c +++ ibm 360, ibm 370, or xerox +++ c c data big/z7fffffffffffffff/, eta/z0010000000000000/, c 1 machep/z3410000000000000/ c c +++ data general +++ c c data big/0.7237005577d+76/, eta/0.5397605347d-78/, c 1 machep/2.22044605d-16/ c c +++ dec 11 +++ c c data big/1.7d+38/, eta/2.938735878d-39/, machep/2.775557562d-17/ c c +++ hp3000 +++ c c data big/1.157920892d+77/, eta/8.636168556d-78/, c 1 machep/5.551115124d-17/ c c +++ honeywell +++ c c data big/1.69d+38/, eta/5.9d-39/, machep/2.1680435d-19/ c c +++ dec10 +++ c c data big/"377777100000000000000000/, c 1 eta/"002400400000000000000000/, c 2 machep/"104400000000000000000000/ c c +++ burroughs +++ c c data big/o0777777777777777,o7777777777777777/, c 1 eta/o1771000000000000,o7770000000000000/, c 2 machep/o1451000000000000,o0000000000000000/ c c +++ control data +++ c c data big/37767777777777777777b,37167777777777777777b/, c 1 eta/00014000000000000000b,00000000000000000000b/, c 2 machep/15614000000000000000b,15010000000000000000b/ c c +++ prime +++ c c data big/1.0d+9786/, eta/1.0d-9860/, machep/1.4210855d-14/ c c +++ univac +++ c c data big/8.988d+307/, eta/1.2d-308/, machep/1.734723476d-18/ c c +++ vax +++ c data big/1.7d+38/, eta/2.939d-39/, machep/1.3877788d-17/ c c +++ cray 1 +++ c c data bigi(1)/577767777777777777777b/, c 1 bigi(2)/000007777777777777776b/, c 2 etai(1)/200004000000000000000b/, c 3 etai(2)/000000000000000000000b/, c 4 machei(1)/377224000000000000000b/, c 5 machei(2)/000000000000000000000b/ c c +++ port library -- requires more than just a data statement... +++ c c external d1mach c double precision d1mach, zero c data big/0.d+0/, eta/0.d+0/, machep/0.d+0/, zero/0.d+0/ c if (big .gt. zero) go to 1 c big = d1mach(2) c eta = d1mach(1) c machep = d1mach(4) c1 continue c c +++ end of port +++ c c------------------------------- body -------------------------------- c go to (10, 20, 30, 40, 50, 60), k c 10 rmdcon = eta go to 999 c 20 rmdcon = dsqrt(256.d+0*eta)/16.d+0 go to 999 c 30 rmdcon = machep go to 999 c 40 rmdcon = dsqrt(machep) go to 999 c 50 rmdcon = dsqrt(big/256.d+0)*16.d+0 go to 999 c 60 rmdcon = big c 999 return c *** last card of rmdcon follows *** end