LAPACK
3.5.0
LAPACK: Linear Algebra PACKage

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Functions/Subroutines  
DOUBLE PRECISION function  dlamch (CMACH) 
DLAMCH More...  
DOUBLE PRECISION function  dlamc3 (A, B) 
DLAMC3 More...  
DOUBLE PRECISION function dlamc3  (  double precision  A, 
double precision  B  
) 
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.
[in]  A  A is a DOUBLE PRECISION 
[in]  B  B is a DOUBLE PRECISION The values A and B. 
Definition at line 172 of file dlamch.f.
DOUBLE PRECISION function dlamch  (  character  CMACH  ) 
DLAMCH
DLAMCH determines double precision machine parameters.
[in]  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**(emin1) emax = largest exponent before overflow rmax = overflow threshold  (base**emax)*(1eps) 
Definition at line 64 of file dlamch.f.