/* Test file for mpfr_factorial.
Copyright 2001-2017 Free Software Foundation, Inc.
Contributed by the AriC and Caramba projects, INRIA.
This file is part of the GNU MPFR Library.
The GNU 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 3 of the License, or (at your
option) any later version.
The GNU 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 GNU MPFR Library; see the file COPYING.LESSER. If not, see
http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
#include <stdio.h>
#include <stdlib.h>
#include "mpfr-test.h"
#define TEST_FUNCTION mpfr_fac_ui
static void
special (void)
{
mpfr_t x, y;
int inex;
mpfr_init (x);
mpfr_init (y);
mpfr_set_prec (x, 21);
mpfr_set_prec (y, 21);
mpfr_fac_ui (x, 119, MPFR_RNDZ);
mpfr_set_str_binary (y, "0.101111101110100110110E654");
if (mpfr_cmp (x, y))
{
printf ("Error in mpfr_fac_ui (119)\n");
exit (1);
}
mpfr_set_prec (y, 206);
inex = mpfr_fac_ui (y, 767, MPFR_RNDN);
mpfr_set_prec (x, 206);
mpfr_set_str_binary (x, "0.110111100001000001101010010001000111000100000100111000010011100011011111001100011110101000111101101100110001001100110100001001111110000101010000100100011100010011101110000001000010001100010000101001111E6250");
if (mpfr_cmp (x, y))
{
printf ("Error in mpfr_fac_ui (767)\n");
exit (1);
}
if (inex <= 0)
{
printf ("Wrong flag for mpfr_fac_ui (767)\n");
exit (1);
}
mpfr_set_prec (y, 202);
mpfr_fac_ui (y, 69, MPFR_RNDU);
mpfr_clear (x);
mpfr_clear (y);
}
static void
test_int (void)
{
unsigned long n0 = 1, n1 = 80, n;
mpz_t f;
mpfr_t x, y;
mpfr_prec_t prec_f, p;
int r;
int inex1, inex2;
mpz_init (f);
mpfr_init (x);
mpfr_init (y);
mpz_fac_ui (f, n0 - 1);
for (n = n0; n <= n1; n++)
{
mpz_mul_ui (f, f, n); /* f = n! */
prec_f = mpz_sizeinbase (f, 2) - mpz_scan1 (f, 0);
for (p = MPFR_PREC_MIN; p <= prec_f; p++)
{
mpfr_set_prec (x, p);
mpfr_set_prec (y, p);
for (r = 0; r < MPFR_RND_MAX; r++)
{
inex1 = mpfr_fac_ui (x, n, (mpfr_rnd_t) r);
inex2 = mpfr_set_z (y, f, (mpfr_rnd_t) r);
if (mpfr_cmp (x, y))
{
printf ("Error for n=%lu prec=%lu rnd=%s\n",
n, (unsigned long) p, mpfr_print_rnd_mode ((mpfr_rnd_t) r));
exit (1);
}
if ((inex1 < 0 && inex2 >= 0) || (inex1 == 0 && inex2 != 0)
|| (inex1 > 0 && inex2 <= 0))
{
printf ("Wrong inexact flag for n=%lu prec=%lu rnd=%s\n",
n, (unsigned long) p, mpfr_print_rnd_mode ((mpfr_rnd_t) r));
exit (1);
}
}
}
}
mpz_clear (f);
mpfr_clear (x);
mpfr_clear (y);
}
static void
overflowed_fac0 (void)
{
mpfr_t x, y;
int inex, rnd, err = 0;
mpfr_exp_t old_emax;
old_emax = mpfr_get_emax ();
mpfr_init2 (x, 8);
mpfr_init2 (y, 8);
mpfr_set_ui (y, 1, MPFR_RNDN);
mpfr_nextbelow (y);
set_emax (0); /* 1 is not representable. */
RND_LOOP (rnd)
{
mpfr_clear_flags ();
inex = mpfr_fac_ui (x, 0, (mpfr_rnd_t) rnd);
if (! mpfr_overflow_p ())
{
printf ("Error in overflowed_fac0 (rnd = %s):\n"
" The overflow flag is not set.\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) rnd));
err = 1;
}
if (rnd == MPFR_RNDZ || rnd == MPFR_RNDD)
{
if (inex >= 0)
{
printf ("Error in overflowed_fac0 (rnd = %s):\n"
" The inexact value must be negative.\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) rnd));
err = 1;
}
if (! mpfr_equal_p (x, y))
{
printf ("Error in overflowed_fac0 (rnd = %s):\n"
" Got ", mpfr_print_rnd_mode ((mpfr_rnd_t) rnd));
mpfr_print_binary (x);
printf (" instead of 0.11111111E0.\n");
err = 1;
}
}
else
{
if (inex <= 0)
{
printf ("Error in overflowed_fac0 (rnd = %s):\n"
" The inexact value must be positive.\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) rnd));
err = 1;
}
if (! (mpfr_inf_p (x) && MPFR_SIGN (x) > 0))
{
printf ("Error in overflowed_fac0 (rnd = %s):\n"
" Got ", mpfr_print_rnd_mode ((mpfr_rnd_t) rnd));
mpfr_print_binary (x);
printf (" instead of +Inf.\n");
err = 1;
}
}
}
set_emax (old_emax);
if (err)
exit (1);
mpfr_clear (x);
mpfr_clear (y);
}
int
main (int argc, char *argv[])
{
unsigned int prec, err, yprec, n, k, zeros;
int rnd;
mpfr_t x, y, z, t;
int inexact;
tests_start_mpfr ();
special ();
test_int ();
mpfr_init (x);
mpfr_init (y);
mpfr_init (z);
mpfr_init (t);
mpfr_fac_ui (y, 0, MPFR_RNDN);
if (mpfr_cmp_ui (y, 1))
{
printf ("mpfr_fac_ui(0) does not give 1\n");
exit (1);
}
for (prec = 2; prec <= 100; prec++)
{
mpfr_set_prec (x, prec);
mpfr_set_prec (z, prec);
mpfr_set_prec (t, prec);
yprec = prec + 10;
mpfr_set_prec (y, yprec);
for (n = 0; n < 50; n++)
for (rnd = 0; rnd < MPFR_RND_MAX; rnd++)
{
inexact = mpfr_fac_ui (y, n, (mpfr_rnd_t) rnd);
err = (rnd == MPFR_RNDN) ? yprec + 1 : yprec;
if (mpfr_can_round (y, err, (mpfr_rnd_t) rnd, (mpfr_rnd_t) rnd, prec))
{
mpfr_set (t, y, (mpfr_rnd_t) rnd);
inexact = mpfr_fac_ui (z, n, (mpfr_rnd_t) rnd);
/* fact(n) ends with floor(n/2)+floor(n/4)+... zeros */
for (k=n/2, zeros=0; k; k >>= 1)
zeros += k;
if (MPFR_EXP(y) <= (mpfr_exp_t) (prec + zeros))
/* result should be exact */
{
if (inexact)
{
printf ("Wrong inexact flag: expected exact\n");
exit (1);
}
}
else /* result is inexact */
{
if (!inexact)
{
printf ("Wrong inexact flag: expected inexact\n");
printf ("n=%u prec=%u\n", n, prec);
mpfr_print_binary(z); puts ("");
exit (1);
}
}
if (mpfr_cmp (t, z))
{
printf ("results differ for x=");
mpfr_out_str (stdout, 2, prec, x, MPFR_RNDN);
printf (" prec=%u rnd_mode=%s\n", prec,
mpfr_print_rnd_mode ((mpfr_rnd_t) rnd));
printf (" got ");
mpfr_out_str (stdout, 2, prec, z, MPFR_RNDN);
puts ("");
printf (" expected ");
mpfr_out_str (stdout, 2, prec, t, MPFR_RNDN);
puts ("");
printf (" approximation was ");
mpfr_print_binary (y);
puts ("");
exit (1);
}
}
}
}
mpfr_clear (x);
mpfr_clear (y);
mpfr_clear (z);
mpfr_clear (t);
overflowed_fac0 ();
tests_end_mpfr ();
return 0;
}