Ich verwende Windows Vista 64 Bit.How to Know Machine abhängige Konstanten
Ich brauche eine Fortran-Datei zu erstellen, für die muss ich diese Datei bearbeiten, um meine Maschine ‚maschinenabhängige Konstanten‘
In dieser Datei übereinstimmen, ich die folgenden Informationen haben. Alle Vorschläge wären von großer Hilfe. Dank
C Explanation of machine-dependent constants
C
C XINF = largest positive machine number
C XMAX1 = beta ** (p-1), where beta is the radix for the
C floating-point system, and p is the number of base-beta
C digits in the floating-point significand. This is an
C upper bound on non-integral floating-point numbers, and
C the negative of the lower bound on acceptable negative
C arguments for PSI. If rounding is necessary, round this
C value down.
C XMIN1 = the smallest in magnitude acceptable argument. We
C recommend XMIN1 = MAX(1/XINF,xmin) rounded up, where
C xmin is the smallest positive floating-point number.
C XSMALL = absolute argument below which PI*COTAN(PI*X) may be
C represented by 1/X. We recommend XSMALL < sqrt(3 eps)/pi,
C where eps is the smallest positive number such that
C 1+eps > 1.
C XLARGE = argument beyond which PSI(X) may be represented by
C LOG(X). The solution to the equation
C x*ln(x) = beta ** p
C is a safe value.
C
C Approximate values for some important machines are
C
C beta p eps xmin XINF
C
C CDC 7600 (S.P.) 2 48 7.11E-15 3.13E-294 1.26E+322
C CRAY-1 (S.P.) 2 48 7.11E-15 4.58E-2467 5.45E+2465
C IEEE (IBM/XT,
C SUN, etc.) (S.P.) 2 24 1.19E-07 1.18E-38 3.40E+38
C IEEE (IBM/XT,
C SUN, etc.) (D.P.) 2 53 1.11D-16 2.23E-308 1.79D+308
C IBM 3033 (D.P.) 16 14 1.11D-16 5.40D-79 7.23D+75
C SUN 3/160 (D.P.) 2 53 1.11D-16 2.23D-308 1.79D+308
C VAX 11/780 (S.P.) 2 24 5.96E-08 2.94E-39 1.70E+38
C (D.P.) 2 56 1.39D-17 2.94D-39 1.70D+38
C (G Format) (D.P.) 2 53 1.11D-16 5.57D-309 8.98D+307
C
C XMIN1 XMAX1 XSMALL XLARGE
C
C CDC 7600 (S.P.) 3.13E-294 1.40E+14 4.64E-08 9.42E+12
C CRAY-1 (S.P.) 1.84E-2466 1.40E+14 4.64E-08 9.42E+12
C IEEE (IBM/XT,
C SUN, etc.) (S.P.) 1.18E-38 8.38E+06 1.90E-04 1.20E+06
C IEEE (IBM/XT,
C SUN, etc.) (D.P.) 2.23D-308 4.50D+15 5.80D-09 2.71D+14
C IBM 3033 (D.P.) 1.39D-76 4.50D+15 5.80D-09 2.05D+15
C SUN 3/160 (D.P.) 2.23D-308 4.50D+15 5.80D-09 2.71D+14
C VAX 11/780 (S.P.) 5.89E-39 8.38E+06 1.35E-04 1.20E+06
C (D.P.) 5.89D-39 3.60D+16 2.05D-09 2.05D+15
C (G Format) (D.P.) 1.12D-308 4.50D+15 5.80D-09 2.71D+14
C
Danke für die Richtung, Rook. – metalhawk