File: [local] / OpenXM_contrib / gmp / mpfr / tests / Attic / tget_d.c (download)
Revision 1.1.1.1 (vendor branch), Mon Aug 25 16:06:10 2003 UTC (21 years, 1 month ago) by ohara
Branch: GMP
CVS Tags: VERSION_4_1_2, RELEASE_1_2_3, RELEASE_1_2_2_KNOPPIX_b, RELEASE_1_2_2_KNOPPIX Changes since 1.1: +0 -0
lines
Import gmp 4.1.2
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/* Test file for mpfr_get_d
Copyright 1999, 2000, 2001, 2002 Free Software Foundation.
This file is part of the MPFR Library.
The MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or (at your
option) any later version.
The MPFR Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the MPFR Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include <stdio.h>
#include <stdlib.h>
#include <float.h>
#include "gmp.h"
#include "gmp-impl.h"
#include "mpfr.h"
#include "mpfr-impl.h"
#include "mpfr-test.h"
int check_denorms _PROTO ((void));
int
check_denorms ()
{
mp_rnd_t rnd_mode;
mpfr_t x;
double d, d2, dd, f;
int fail = 0, k, n;
mpfr_init2 (x, BITS_PER_MP_LIMB);
for (rnd_mode = 0; rnd_mode <= 3; rnd_mode++)
{
#ifdef MPFR_HAVE_FESETROUND
mpfr_set_machine_rnd_mode (rnd_mode);
#else
if (rnd_mode)
break; /* second iteration */
rnd_mode = GMP_RNDN;
#endif
for (k = -17; k <= 17; k += 2)
{
d = k * DBL_MIN; /* k * 2^(-1022) */
f = 1.0;
mpfr_set_si (x, k, GMP_RNDN);
mpfr_div_2exp (x, x, 1022, GMP_RNDN); /* k * 2^(-1022) */
for (n = 0; n <= 58; n++)
{
d2 = d * f;
dd = mpfr_get_d (x, rnd_mode);
if (d2 != dd) /* should be k * 2^(-1022-n) for n < 53 */
{
fprintf (stderr,
"Wrong result for %d * 2^(%d), rnd_mode %d\n",
k, -1022-n, rnd_mode);
fprintf (stderr, "got %.20e instead of %.20e\n", dd, d2);
fail = 1;
}
f *= 0.5;
mpfr_div_2exp (x, x, 1, GMP_RNDN);
}
}
}
mpfr_clear (x);
return fail;
}
int
main (void)
{
#ifdef MPFR_HAVE_FESETROUND
mpfr_t half, x, y;
mp_rnd_t rnd_mode;
#endif
mpfr_test_init ();
#ifdef MPFR_HAVE_FESETROUND
mpfr_init2(half, 2);
mpfr_set_ui(half, 1, GMP_RNDZ);
mpfr_div_2ui(half, half, 1, GMP_RNDZ); /* has exponent 0 */
mpfr_init2(x, 128);
mpfr_init2(y, 128);
for (rnd_mode = 0; rnd_mode <= 3; rnd_mode++)
{
int i, j, si, sj;
double di, dj;
mpfr_set_machine_rnd_mode (rnd_mode);
for (i = 1, di = 0.25; i < 127; i++, di *= 0.5)
for (si = 0; si <= 1; si++)
{
mpfr_div_2ui (x, half, i, GMP_RNDZ);
(si ? mpfr_sub : mpfr_add)(x, half, x, GMP_RNDZ);
/* x = 1/2 +/- 1/2^(1+i) */
for (j = i+1, dj = di * 0.5; j < 128 && j < i+53; j++, dj *= 0.5)
for (sj = 0; sj <= 1; sj++)
{
double c, d, dd;
int exp;
char *f;
mpfr_div_2ui (y, half, j, GMP_RNDZ);
(sj ? mpfr_sub : mpfr_add)(y, x, y, GMP_RNDZ);
/* y = 1/2 +/- 1/2^(1+i) +/- 1/2^(1+j) */
exp = (LONG_RAND() % 47) - 23;
mpfr_mul_2si (y, y, exp, GMP_RNDZ);
if (mpfr_inexflag_p())
{
fprintf(stderr, "Error in tget_d: inexact flag for "
"(i,si,j,sj,rnd,exp) = (%d,%d,%d,%d,%d,%d)\n",
i, si, j, sj, rnd_mode, exp);
exit(1);
}
dd = si != sj ? di - dj : di + dj;
d = si ? 0.5 - dd : 0.5 + dd;
if ((LONG_RAND() / 1024) & 1)
{
c = mpfr_get_d (y, rnd_mode);
f = "mpfr_get_d";
}
else
{
exp = (LONG_RAND() % 47) - 23;
c = mpfr_get_d3 (y, exp, rnd_mode);
f = "mpfr_get_d3";
if (si) /* then real d < 0.5 */
d *= sj && i == 1 ? 4 : 2; /* normalize real d */
}
if (exp > 0)
d *= 1 << exp;
if (exp < 0)
d /= 1 << -exp;
if (c != d)
{
fprintf (stderr, "Error in tget_d (%s) for "
"(i,si,j,sj,rnd,exp) = (%d,%d,%d,%d,%d,%d)\n"
"got %.25Le instead of %.25Le\n"
"Difference: %.19e\n",
f, i, si, j, sj, rnd_mode, exp,
(long double) c, (long double) d, d - c);
exit (1);
}
}
}
}
mpfr_clear(half);
mpfr_clear(x);
mpfr_clear(y);
#endif
if (check_denorms ())
exit (1);
return 0;
}