aboutsummaryrefslogtreecommitdiff
path: root/tests/turandom.c
diff options
context:
space:
mode:
Diffstat (limited to 'tests/turandom.c')
-rw-r--r--tests/turandom.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/tests/turandom.c b/tests/turandom.c
new file mode 100644
index 0000000..b99587b
--- /dev/null
+++ b/tests/turandom.c
@@ -0,0 +1,249 @@
+/* Test file for mpfr_urandom
+
+Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
+Contributed by the AriC and Caramel 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"
+
+static void
+test_urandom (long nbtests, mpfr_prec_t prec, mpfr_rnd_t rnd, long bit_index,
+ int verbose)
+{
+ mpfr_t x;
+ int *tab, size_tab, k, sh, xn;
+ double d, av = 0, var = 0, chi2 = 0, th;
+ mpfr_exp_t emin;
+ mp_size_t limb_index = 0;
+ mp_limb_t limb_mask = 0;
+ long count = 0;
+ int i;
+ int inex = 1;
+
+ size_tab = (nbtests >= 1000 ? nbtests / 50 : 20);
+ tab = (int *) calloc (size_tab, sizeof(int));
+ if (tab == NULL)
+ {
+ fprintf (stderr, "trandom: can't allocate memory in test_urandom\n");
+ exit (1);
+ }
+
+ mpfr_init2 (x, prec);
+ xn = 1 + (prec - 1) / mp_bits_per_limb;
+ sh = xn * mp_bits_per_limb - prec;
+ if (bit_index >= 0 && bit_index < prec)
+ {
+ /* compute the limb index and limb mask to fetch the bit #bit_index */
+ limb_index = (prec - bit_index) / mp_bits_per_limb;
+ i = 1 + bit_index - (bit_index / mp_bits_per_limb) * mp_bits_per_limb;
+ limb_mask = MPFR_LIMB_ONE << (mp_bits_per_limb - i);
+ }
+
+ for (k = 0; k < nbtests; k++)
+ {
+ i = mpfr_urandom (x, RANDS, rnd);
+ inex = (i != 0) && inex;
+ /* check that lower bits are zero */
+ if (MPFR_MANT(x)[0] & MPFR_LIMB_MASK(sh) && !MPFR_IS_ZERO (x))
+ {
+ printf ("Error: mpfr_urandom() returns invalid numbers:\n");
+ mpfr_print_binary (x); puts ("");
+ exit (1);
+ }
+ /* check that the value is in [0,1] */
+ if (mpfr_cmp_ui (x, 0) < 0 || mpfr_cmp_ui (x, 1) > 0)
+ {
+ printf ("Error: mpfr_urandom() returns number outside [0, 1]:\n");
+ mpfr_print_binary (x); puts ("");
+ exit (1);
+ }
+
+ d = mpfr_get_d1 (x); av += d; var += d*d;
+ i = (int)(size_tab * d);
+ if (d == 1.0) i --;
+ tab[i]++;
+
+ if (limb_mask && (MPFR_MANT (x)[limb_index] & limb_mask))
+ count ++;
+ }
+
+ if (inex == 0)
+ {
+ /* one call in the loop pretended to return an exact number! */
+ printf ("Error: mpfr_urandom() returns a zero ternary value.\n");
+ exit (1);
+ }
+
+ /* coverage test */
+ emin = mpfr_get_emin ();
+ for (k = 0; k < 5; k++)
+ {
+ set_emin (k+1);
+ inex = mpfr_urandom (x, RANDS, rnd);
+ if (( (rnd == MPFR_RNDZ || rnd == MPFR_RNDD)
+ && (!MPFR_IS_ZERO (x) || inex != -1))
+ || ((rnd == MPFR_RNDU || rnd == MPFR_RNDA)
+ && (mpfr_cmp_ui (x, 1 << k) != 0 || inex != +1))
+ || (rnd == MPFR_RNDN
+ && (k > 0 || mpfr_cmp_ui (x, 1 << k) != 0 || inex != +1)
+ && (!MPFR_IS_ZERO (x) || inex != -1)))
+ {
+ printf ("Error: mpfr_urandom() do not handle correctly a restricted"
+ " exponent range.\nrounding mode: %s\nternary value: %d\n"
+ "random value: ", mpfr_print_rnd_mode (rnd), inex);
+ mpfr_print_binary (x); puts ("");
+ exit (1);
+ }
+ }
+ set_emin (emin);
+
+ mpfr_clear (x);
+ if (!verbose)
+ {
+ free(tab);
+ return;
+ }
+
+ av /= nbtests;
+ var = (var / nbtests) - av * av;
+
+ th = (double)nbtests / size_tab;
+ printf ("Average = %.5f\nVariance = %.5f\n", av, var);
+ printf ("Repartition for urandom with rounding mode %s. "
+ "Each integer should be close to %d.\n",
+ mpfr_print_rnd_mode (rnd), (int)th);
+
+ for (k = 0; k < size_tab; k++)
+ {
+ chi2 += (tab[k] - th) * (tab[k] - th) / th;
+ printf("%d ", tab[k]);
+ if (((k+1) & 7) == 0)
+ printf("\n");
+ }
+
+ printf("\nChi2 statistics value (with %d degrees of freedom) : %.5f\n",
+ size_tab - 1, chi2);
+
+ if (limb_mask)
+ printf ("Bit #%ld is set %ld/%ld = %.1f %% of time\n",
+ bit_index, count, nbtests, count * 100.0 / nbtests);
+
+ puts ("");
+
+ free(tab);
+ return;
+}
+
+/* problem reported by Carl Witty */
+static void
+bug20100914 (void)
+{
+ mpfr_t x;
+ gmp_randstate_t s;
+
+#if __MPFR_GMP(4,2,0)
+# define C1 "0.8488312"
+# define C2 "0.8156509"
+#else
+# define C1 "0.6485367"
+# define C2 "0.9362717"
+#endif
+
+ gmp_randinit_default (s);
+ gmp_randseed_ui (s, 42);
+ mpfr_init2 (x, 17);
+ mpfr_urandom (x, s, MPFR_RNDN);
+ if (mpfr_cmp_str1 (x, C1) != 0)
+ {
+ printf ("Error in bug20100914, expected " C1 ", got ");
+ mpfr_out_str (stdout, 10, 0, x, MPFR_RNDN);
+ printf ("\n");
+ exit (1);
+ }
+ mpfr_urandom (x, s, MPFR_RNDN);
+ if (mpfr_cmp_str1 (x, C2) != 0)
+ {
+ printf ("Error in bug20100914, expected " C2 ", got ");
+ mpfr_out_str (stdout, 10, 0, x, MPFR_RNDN);
+ printf ("\n");
+ exit (1);
+ }
+ mpfr_clear (x);
+ gmp_randclear (s);
+}
+
+int
+main (int argc, char *argv[])
+{
+ long nbtests;
+ mpfr_prec_t prec;
+ int verbose = 0;
+ int rnd;
+ long bit_index;
+
+ tests_start_mpfr ();
+
+ if (argc > 1)
+ verbose = 1;
+
+ nbtests = 10000;
+ if (argc > 1)
+ {
+ long a = atol(argv[1]);
+ if (a != 0)
+ nbtests = a;
+ }
+
+ if (argc <= 2)
+ prec = 1000;
+ else
+ prec = atol(argv[2]);
+
+ if (argc <= 3)
+ bit_index = -1;
+ else
+ {
+ bit_index = atol(argv[3]);
+ if (bit_index >= prec)
+ {
+ printf ("Warning. Cannot compute the bit frequency: the given bit "
+ "index (= %ld) is not less than the precision (= %ld).\n",
+ bit_index, (long) prec);
+ bit_index = -1;
+ }
+ }
+
+ RND_LOOP(rnd)
+ {
+ test_urandom (nbtests, prec, (mpfr_rnd_t) rnd, bit_index, verbose);
+
+ if (argc == 1) /* check also small precision */
+ {
+ test_urandom (nbtests, 2, (mpfr_rnd_t) rnd, -1, 0);
+ }
+ }
+
+ bug20100914 ();
+
+ tests_end_mpfr ();
+ return 0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-14 19:16:06 +0000