Make dpmpar portable using epsilon, tiny and huge

Author: certik

src/dpmpar.f

@@ -31,143 +31,11 @@ double precision function dpmpar(i)
 c     Burton S. Garbow, Kenneth E. Hillstrom, Jorge J. More'
 c
 c     **********
-      integer mcheps(4)
-      integer minmag(4)
-      integer maxmag(4)
+
       double precision dmach(3)
-      equivalence (dmach(1),mcheps(1))
-      equivalence (dmach(2),minmag(1))
-      equivalence (dmach(3),maxmag(1))
-c
-c     Machine constants for the IBM 360/370 series,
-c     the Amdahl 470/V6, the ICL 2900, the Itel AS/6,
-c     the Xerox Sigma 5/7/9 and the Sel systems 85/86.
-c
-c     data mcheps(1),mcheps(2) / z34100000, z00000000 /
-c     data minmag(1),minmag(2) / z00100000, z00000000 /
-c     data maxmag(1),maxmag(2) / z7fffffff, zffffffff /
-c
-c     Machine constants for the Honeywell 600/6000 series.
-c
-c     data mcheps(1),mcheps(2) / o606400000000, o000000000000 /
-c     data minmag(1),minmag(2) / o402400000000, o000000000000 /
-c     data maxmag(1),maxmag(2) / o376777777777, o777777777777 /
-c
-c     Machine constants for the CDC 6000/7000 series.
-c
-c     data mcheps(1) / 15614000000000000000b /
-c     data mcheps(2) / 15010000000000000000b /
-c
-c     data minmag(1) / 00604000000000000000b /
-c     data minmag(2) / 00000000000000000000b /
-c
-c     data maxmag(1) / 37767777777777777777b /
-c     data maxmag(2) / 37167777777777777777b /
-c
-c     Machine constants for the PDP-10 (KA processor).
-c
-c     data mcheps(1),mcheps(2) / "114400000000, "000000000000 /
-c     data minmag(1),minmag(2) / "033400000000, "000000000000 /
-c     data maxmag(1),maxmag(2) / "377777777777, "344777777777 /
-c
-c     Machine constants for the PDP-10 (KI processor).
-c
-c     data mcheps(1),mcheps(2) / "104400000000, "000000000000 /
-c     data minmag(1),minmag(2) / "000400000000, "000000000000 /
-c     data maxmag(1),maxmag(2) / "377777777777, "377777777777 /
-c
-c     Machine constants for the PDP-11. 
-c
-c     data mcheps(1),mcheps(2) /   9472,      0 /
-c     data mcheps(3),mcheps(4) /      0,      0 /
-c
-c     data minmag(1),minmag(2) /    128,      0 /
-c     data minmag(3),minmag(4) /      0,      0 /
-c
-c     data maxmag(1),maxmag(2) /  32767,     -1 /
-c     data maxmag(3),maxmag(4) /     -1,     -1 /
-c
-c     Machine constants for the Burroughs 6700/7700 systems.
-c
-c     data mcheps(1) / o1451000000000000 /
-c     data mcheps(2) / o0000000000000000 /
-c
-c     data minmag(1) / o1771000000000000 /
-c     data minmag(2) / o7770000000000000 /
-c
-c     data maxmag(1) / o0777777777777777 /
-c     data maxmag(2) / o7777777777777777 /
-c
-c     Machine constants for the Burroughs 5700 system.
-c
-c     data mcheps(1) / o1451000000000000 /
-c     data mcheps(2) / o0000000000000000 /
-c
-c     data minmag(1) / o1771000000000000 /
-c     data minmag(2) / o0000000000000000 /
-c
-c     data maxmag(1) / o0777777777777777 /
-c     data maxmag(2) / o0007777777777777 /
-c
-c     Machine constants for the Burroughs 1700 system.
-c
-c     data mcheps(1) / zcc6800000 /
-c     data mcheps(2) / z000000000 /
-c
-c     data minmag(1) / zc00800000 /
-c     data minmag(2) / z000000000 /
-c
-c     data maxmag(1) / zdffffffff /
-c     data maxmag(2) / zfffffffff /
-c
-c     Machine constants for the Univac 1100 series.
-c
-c     data mcheps(1),mcheps(2) / o170640000000, o000000000000 /
-c     data minmag(1),minmag(2) / o000040000000, o000000000000 /
-c     data maxmag(1),maxmag(2) / o377777777777, o777777777777 /
-c
-c     Machine constants for the Data General Eclipse S/200.
-c
-c     Note - it may be appropriate to include the following card -
-c     static dmach(3)
-c
-c     data minmag/20k,3*0/,maxmag/77777k,3*177777k/
-c     data mcheps/32020k,3*0/
-c
-c     Machine constants for the Harris 220.
-c
-c     data mcheps(1),mcheps(2) / '20000000, '00000334 /
-c     data minmag(1),minmag(2) / '20000000, '00000201 /
-c     data maxmag(1),maxmag(2) / '37777777, '37777577 /
-c
-c     Machine constants for the Cray-1.
-c
-c     data mcheps(1) / 0376424000000000000000b /
-c     data mcheps(2) / 0000000000000000000000b /
-c
-c     data minmag(1) / 0200034000000000000000b /
-c     data minmag(2) / 0000000000000000000000b /
-c
-c     data maxmag(1) / 0577777777777777777777b /
-c     data maxmag(2) / 0000007777777777777776b /
-c
-c     Machine constants for the Prime 400.
-c
-c     data mcheps(1),mcheps(2) / :10000000000, :00000000123 /
-c     data minmag(1),minmag(2) / :10000000000, :00000100000 /
-c     data maxmag(1),maxmag(2) / :17777777777, :37777677776 /
-c
-c     Machine constants for the VAX-11.
-c
-c     data mcheps(1),mcheps(2) /   9472,  0 /
-c     data minmag(1),minmag(2) /    128,  0 /
-c     data maxmag(1),maxmag(2) / -32769, -1 /
-c
-c     Machine constants for IEEE machines.
-c
-      data dmach(1) /2.22044604926d-16/
-      data dmach(2) /2.22507385852d-308/
-      data dmach(3) /1.79769313485d+308/
+      dmach(1) = epsilon(1d0)
+      dmach(2) = tiny(1d0)
+      dmach(3) = huge(1d0)
 c
       dpmpar = dmach(i)
       return