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PDLAMCH(l)			       )			    PDLAMCH(l)

NAME
       PDLAMCH - determine double precision machine parameters

SYNOPSIS
       DOUBLE PRECISION	FUNCTION PDLAMCH( ICTXT, CMACH )

	   CHARACTER	CMACH

	   INTEGER	ICTXT

PURPOSE
       PDLAMCH determines double precision machine parameters.

ARGUMENTS
       ICTXT   (global input) INTEGER
	       The BLACS context handle	in which the computation takes place.

       CMACH   (global input) CHARACTER*1
	       Specifies the value to be returned by PDLAMCH:
	       = 'E' or	'e',   PDLAMCH := eps
	       = 'S' or	's ,   PDLAMCH := sfmin
	       = 'B' or	'b',   PDLAMCH := base
	       = 'P' or	'p',   PDLAMCH := eps*base
	       = 'N' or	'n',   PDLAMCH := t
	       = 'R' or	'r',   PDLAMCH := rnd
	       = 'M' or	'm',   PDLAMCH := emin
	       = 'U' or	'u',   PDLAMCH := rmin
	       = 'L' or	'l',   PDLAMCH := emax
	       = 'O' or	'o',   PDLAMCH := 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 mantissa rnd   = 1.0 when rounding occurs in addi-
	     tion, 0.0 otherwise emin  = minimum exponent before (gradual) un-
	     derflow  rmin   =	underflow  threshold  -	base**(emin-1) emax  =
	     largest exponent before overflow rmax  =  overflow	 threshold   -
	     (base**emax)*(1-eps)

ScaLAPACK version 1.7		13 August 2001			    PDLAMCH(l)

NAME | SYNOPSIS | PURPOSE | ARGUMENTS

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