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lamch(3) Library Functions Manual 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 DLAMCHF77 deprecated

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.

Purpose:

!>
!> DLAMCHF77 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.

Definition at line 68 of file dlamch.f.

real function SLAMCH (character cmach)

SLAMCH SLAMCHF77 deprecated

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.

Purpose:

!>
!> SLAMCH determines single precision machine parameters.
!>

Parameters

CMACH 

!>          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.

Definition at line 67 of file slamch.f.

Author

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