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dlamch.f(3)                         LAPACK                         dlamch.f(3)

NAME

dlamch.f -

SYNOPSIS

Functions/Subroutines DOUBLE PRECISION function dlamch (CMACH) DLAMCH DOUBLE PRECISION function dlamc3 (A, B) DLAMC3 Function/Subroutine Documentation DOUBLE PRECISION function dlamc3 (double precisionA, double precisionB) DLAMC3 Purpose: DLAMC3 is intended to force A and B to be stored prior to doing the addition of A and B , for use in situations where optimizers might hold one of these in a register. Author: LAPACK is a software package provided by Univ. of Tennessee, Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd.. Date: November 2011 Parameters: A A is a DOUBLE PRECISION B B is a DOUBLE PRECISION The values A and B. Definition at line 172 of file dlamch.f. DOUBLE PRECISION function dlamch (characterCMACH) DLAMCH Purpose: DLAMCH determines double precision machine parameters. Parameters: CMACH 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 mantissa rnd = 1.0 when rounding occurs in addition, 0.0 otherwise emin = minimum exponent before (gradual) underflow rmin = underflow threshold - base**(emin-1) emax = largest exponent before overflow rmax = overflow threshold - (base**emax)*(1-eps) Author: Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Date: November 2011 Definition at line 64 of file dlamch.f. Author Generated automatically by Doxygen for LAPACK from the source code. Version 3.4.2 Sat Nov 16 2013 dlamch.f(3)

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