fpinfo_i(3PI) Sun Interval Performance Library fpinfo_i(3PI)NAMEfpinfo_i - Environmental enquiry.
DESCRIPTION
RESULT = FPINFO ( CMACH, PREC )
The routine FPINFO_I queries for machine-specific floating point char‐
acteristics.
PREC argument can take values:
SINGLE - internal computation performed in single
precision
DOUBLE - internal computation performed in double
precision
INDIGENOUS - internal computation performed in the widest
hardware-supported format available
EXTRA - internal computation performed in format wider
than 80-bits
The CMACH argument values have the following meaning:
BASE - base of the machine
T - number of digits
RND - rounding mode (RESULT = 1 or 0: 1 when proper
rounding occurs in addition, 0 otherwise)
IEEE - IEEE rounding style (RESULT = 1 or 0: 1 when
rounding in addition is in IEEE, 0 otherwise)
EMIN - minimum exponent before (gradual) underflow
EMAX - maximum exponent before overflow
EPS - machine epsilon (if RND=1: EPS=.5*BASE**(1-T),
if RND=0: EPS=BASE**(1-T))
PREC - precision: EPS*BASE
UN - underflow treshold: UN=BASE**EMIN
OV - overflow treshold: OV=BASE**(EMAX+1)*(1-EPS)
SFMIN - safe minimum, such that 1/SFMIN does not overflow
(if 1/OV<UN: SFMIN=UN, else SFMIN=(1+EPS)/OV)
SYNOPSIS
SUBROUTINE FPINFO_I( CMACH, PREC )
TYPE (blas_cmach_type), INTENT(IN) :: CMACH
TYPE (blas_prec_type), INTENT(IN) :: PREC
ARGUMENTSCMACH(input)
Scalar element.
Can take one of the following values:
blas_base | blas_t | blas_rnd | blas_ieee |
blas_emin | blas_emax | blas_eps |
blas_prec | blas_underflow | blas_overflow |
blas_sfmin
Unchanged on exit.
PREC(input)
Scalar element.
Relative machine precision.
Can take one of the following values:
blas_prec_single | blas_prec_double |
blas_prec_indigenous| blas_prec_extra
Unchanged on exit.
6 Mar 2009 fpinfo_i(3PI)
