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#include <config.h>
#include "limits.h"
/* Edited 12/22/97 by Ben Pfaff for PSPP. */
int ipmpar(int*);
/*
-----------------------------------------------------------------------
IPMPAR PROVIDES THE INTEGER MACHINE CONSTANTS FOR THE COMPUTER
THAT IS USED. IT IS ASSUMED THAT THE ARGUMENT I IS AN INTEGER
HAVING ONE OF THE VALUES 1-10. IPMPAR(I) HAS THE VALUE ...
INTEGERS.
ASSUME INTEGERS ARE REPRESENTED IN THE N-DIGIT, BASE-A FORM
SIGN ( X(N-1)*A**(N-1) + ... + X(1)*A + X(0) )
WHERE 0 .LE. X(I) .LT. A FOR I=0,...,N-1.
IPMPAR(1) = A, THE BASE.
IPMPAR(2) = N, THE NUMBER OF BASE-A DIGITS.
IPMPAR(3) = A**N - 1, THE LARGEST MAGNITUDE.
FLOATING-POINT NUMBERS.
IT IS ASSUMED THAT THE SINGLE AND DOUBLE PRECISION FLOATING
POINT ARITHMETICS HAVE THE SAME BASE, SAY B, AND THAT THE
NONZERO NUMBERS ARE REPRESENTED IN THE FORM
SIGN (B**E) * (X(1)/B + ... + X(M)/B**M)
WHERE X(I) = 0,1,...,B-1 FOR I=1,...,M,
X(1) .GE. 1, AND EMIN .LE. E .LE. EMAX.
IPMPAR(4) = B, THE BASE.
SINGLE-PRECISION
IPMPAR(5) = M, THE NUMBER OF BASE-B DIGITS.
IPMPAR(6) = EMIN, THE SMALLEST EXPONENT E.
IPMPAR(7) = EMAX, THE LARGEST EXPONENT E.
DOUBLE-PRECISION
IPMPAR(8) = M, THE NUMBER OF BASE-B DIGITS.
IPMPAR(9) = EMIN, THE SMALLEST EXPONENT E.
IPMPAR(10) = EMAX, THE LARGEST EXPONENT E.
-----------------------------------------------------------------------
TO DEFINE THIS FUNCTION FOR THE COMPUTER BEING USED REMOVE
THE COMMENT DELIMITORS FROM THE DEFINITIONS DIRECTLY BELOW THE NAME
OF THE MACHINE
-----------------------------------------------------------------------
IPMPAR IS AN ADAPTATION OF THE FUNCTION I1MACH, WRITTEN BY
P.A. FOX, A.D. HALL, AND N.L. SCHRYER (BELL LABORATORIES).
IPMPAR WAS FORMED BY A.H. MORRIS (NSWC). THE CONSTANTS ARE
FROM BELL LABORATORIES, NSWC, AND OTHER SOURCES.
-----------------------------------------------------------------------
.. Scalar Arguments ..
*/
int ipmpar(int *i)
{
static int imach[11];
static int ipmpar;
imach[1] = 2;
imach[2] = sizeof (long) * 8 - 1;
imach[3] = INT_MAX;
#if FPREP==FPREP_IEEE754
imach[4] = 2;
imach[5] = 24;
imach[6] = -125;
imach[7] = 128;
imach[8] = 53;
imach[9] = -1021;
imach[10] = 1024;
#else
#error Please define machine-specific constants for your machine.
#endif
ipmpar = imach[*i];
return ipmpar;
}
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