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Updated: June 2017
 
 

dlamch (3p)

Name

dlamch - Determines double precision machine parameters.

Synopsis

DOUBLE PRECISION FUNCTION DLAMCH(CMACH)

CHARACTER*1 CMACH

DOUBLE PRECISION FUNCTION DLAMCH_64(CMACH)

CHARACTER*1 CMACH




F95 INTERFACE
REAL(8) FUNCTION DLAMCH(CMACH)

CHARACTER, INTENT(IN) :: CMACH




C INTERFACE
#include <sunperf.h>

double dlamch(const char);

double dlamch_64(const char);

Description

Oracle Solaris Studio Performance Library                           dlamch(3P)



NAME
       dlamch - Determines double precision machine parameters.


SYNOPSIS
       DOUBLE PRECISION FUNCTION DLAMCH(CMACH)

       CHARACTER*1 CMACH

       DOUBLE PRECISION FUNCTION DLAMCH_64(CMACH)

       CHARACTER*1 CMACH




   F95 INTERFACE
       REAL(8) FUNCTION DLAMCH(CMACH)

       CHARACTER, INTENT(IN) :: CMACH




   C INTERFACE
       #include <sunperf.h>

       double dlamch(const char);

       double dlamch_64(const char);



PURPOSE
       dlamch returns double precision machine paramters.


ARGUMENTS
       CMACH (input)
                 On entry, CMACH specifies the value to be returned.
                 CMACH = 'E' or 'e', eps, relative machine precision
                 CMACH  = 'S' or 's , safe minimum, such that 1/sfmin does not
                 overflow
                 CMACH = 'B' or 'b', base of the machine
                 CMACH = 'P' or 'p', eps * base
                 CMACH = 'N' or 'n', number of (base) digits in the mantissa
                 CMACH = 'R' or 'r', 1.0 when rounding occurs in addition, 0.0
                 otherwise
                 CMACH  =  'M' or 'm', emin, minimum exponent before (gradual)
                 underflow
                 CMACH = 'U' or 'u', underflow threshold - base**(emin-1)
                 CMACH = 'L' or 'l', emax, largest exponent before overflow
                 CMACH   =    'O'    or    'o',    overflow    threshold     -
                 (base**emax)*(1-eps)
                 Unchanged on exit.



                                  7 Nov 2015                        dlamch(3P)