table of contents
| lamch(3) | LAPACK | lamch(3) |
NAME¶
lamch - lamch: machine parameters
SYNOPSIS¶
Functions¶
double precision function dlamch (cmach)
DLAMCH real function slamch (cmach)
SLAMCH
Detailed Description¶
Function Documentation¶
double precision function dlamch (character cmach)¶
DLAMCH
Purpose:
!> !> DLAMCH determines double precision machine parameters. !>
Parameters
CMACH
!> CMACH is 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 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.
real function slamch (character cmach)¶
SLAMCH
Purpose:
!> !> SLAMCH determines single precision machine parameters. !>
Parameters
CMACH
!> CMACH is CHARACTER*1 !> Specifies the value to be returned by SLAMCH: !> = 'E' or 'e', SLAMCH := eps !> = 'S' or 's , SLAMCH := sfmin !> = 'B' or 'b', SLAMCH := base !> = 'P' or 'p', SLAMCH := eps*base !> = 'N' or 'n', SLAMCH := t !> = 'R' or 'r', SLAMCH := rnd !> = 'M' or 'm', SLAMCH := emin !> = 'U' or 'u', SLAMCH := rmin !> = 'L' or 'l', SLAMCH := emax !> = 'O' or 'o', SLAMCH := 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.
Author¶
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| Tue Jun 30 2026 04:57:07 | Version 3.12.0 |