DLAMCH - determine double precision machine parameters


SYNOPSIS

       DOUBLE PRECISION FUNCTION DLAMCH( CMACH )

           CHARACTER    CMACH


PURPOSE

       DLAMCH determines double precision machine parameters.


ARGUMENTS

       CMACH   (input) CHARACTER*1
               Specifies the value to be returned by DLAMCH:
               = 'E' or 'e',   DLAMCH := eps
               = 'S' or 's ,   DLAMCH := sfmin
               = 'B' or 'b',   DLAMCH := base
               = 'P' or 'p',   DLAMCH := eps*base
               = 'N' or 'n',   DLAMCH := t
               = 'R' or 'r',   DLAMCH := rnd
               = 'M' or 'm',   DLAMCH := emin
               = 'U' or 'u',   DLAMCH := rmin
               = 'L' or 'l',   DLAMCH := emax
               = 'O' or 'o',   DLAMCH := rmax

               where

       eps   = relative machine precision
             sfmin  =  safe  minimum,  such that 1/sfmin does not
             overflow  base   =  base  of  the  machine  prec   =
             eps*base t     = number of (base) digits in the man­
             tissa rnd   = 1.0 when rounding occurs in  addition,
             0.0 otherwise emin  = minimum exponent before (grad­
             ual)  underflow  rmin   =  underflow   threshold   -
             base**(emin-1) emax  = largest exponent before over­
             flow    rmax     =     overflow     threshold      -
             (base**emax)*(1-eps)


Man(1) output converted with man2html