/* Unit tests for grand

 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald

 *

 * This work is provided "as is"; redistribution and modification

 * in whole or in part, in any medium, physical or electronic is

 * permitted without restriction.

 *

 * This work 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.

 *

 * In no event shall the authors or contributors be liable for any

 * direct, indirect, incidental, special, exemplary, or consequential

 * damages (including, but not limited to, procurement of substitute

 * goods or services; loss of use, data, or profits; or business

 * interruption) however caused and on any theory of liability, whether

 * in contract, strict liability, or tort (including negligence or

 * otherwise) arising in any way out of the use of this software, even

 * if advised of the possibility of such damage.

 */

#include "glib.h"

/* Outputs tested against the reference implementation mt19937ar.c from

 * http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/emt19937ar.html

 */

/* Tests for a simple seed, first number is the seed */

const guint32 first_numbers[] = 

{

  0x7a7a7a7a,

  0xfdcc2d54,

  0x3a279ceb,

  0xc4d39c33,

  0xf31895cd,

  0x46ca0afc,

  0x3f5484ff,

  0x54bc9557,

  0xed2c24b1,

  0x84062503,

  0x8f6404b3,

  0x599a94b3,

  0xe46d03d5,

  0x310beb78,

  0x7bee5d08,

  0x760d09be,

  0x59b6e163,

  0xbf6d16ec,

  0xcca5fb54,

  0x5de7259b,

  0x1696330c,

};

/* array seed */

const guint32 seed_array[] =

{

  0x6553375f,

  0xd6b8d43b,

  0xa1e7667f,

  0x2b10117c

};

/* tests for the array seed */

const guint32 array_outputs[] =

{

  0xc22b7dc3,

  0xfdecb8ae,

  0xb4af0738,

  0x516bc6e1,

  0x7e372e91,

  0x2d38ff80,

  0x6096494a,

  0xd162d5a8,

  0x3c0aaa0d,

  0x10e736ae

};

static void

test_rand (void)

{

  guint n;

  guint ones;

  double proportion;

  GRand *rand;

  GRand *copy;

  rand = g_rand_new_with_seed (first_numbers[0]);

  for (n = 1; n < G_N_ELEMENTS (first_numbers); n++)

    g_assert (first_numbers[n] == g_rand_int (rand));

  g_rand_set_seed (rand, 2);

  g_rand_set_seed_array (rand, seed_array, G_N_ELEMENTS (seed_array));

  for (n = 0; n < G_N_ELEMENTS (array_outputs); n++)

    g_assert (array_outputs[n] == g_rand_int (rand));

  copy = g_rand_copy (rand);

  for (n = 0; n < 100; n++)

    g_assert (g_rand_int (copy) == g_rand_int (rand));

  for (n = 1; n < 100000; n++)

    {

      gint32 i;

      gdouble d;

      gboolean b;

      i = g_rand_int_range (rand, 8,16);

      g_assert (i >= 8 && i < 16);

      i = g_random_int_range (8,16);

      g_assert (i >= 8 && i < 16);

      d = g_rand_double (rand);

      g_assert (d >= 0 && d < 1);

      d = g_random_double ();

      g_assert (d >= 0 && d < 1);

      d = g_rand_double_range (rand, -8, 32);

      g_assert (d >= -8 && d < 32);

      d = g_random_double_range (-8, 32);

      g_assert (d >= -8 && d < 32);

      b = g_random_boolean ();

      g_assert (b == TRUE || b  == FALSE);

      b = g_rand_boolean (rand);

      g_assert (b == TRUE || b  == FALSE);     

    }

  /* Statistical sanity check, count the number of ones

   * when getting random numbers in range [0,3) and see

   * that it must be semi-close to 0.25 with a VERY large

   * probability */

  ones = 0;

  for (n = 1; n < 100000; n++)

    {

      if (g_random_int_range (0, 4) == 1)

        ones ++;

    }

  proportion = (double)ones / (double)100000;

  /* 0.025 is overkill, but should suffice to test for some unreasonability */

  g_assert (ABS (proportion - 0.25) < 0.025);

  g_rand_free (rand);

  g_rand_free (copy);

}

static void

test_double_range (void)

{

  gdouble d;

  g_test_bug ("502560");

  d = g_random_double_range (-G_MAXDOUBLE, G_MAXDOUBLE);

  g_assert (-G_MAXDOUBLE <= d);

  g_assert (d < G_MAXDOUBLE);

}

int

main (int   argc,

      char *argv[])

{

  g_test_init (&argc, &argv, NULL);

  g_test_bug_base ("http://bugzilla.gnome.org/");

  g_test_add_func ("/rand/test-rand", test_rand);

  g_test_add_func ("/rand/double-range", test_double_range);

  return g_test_run();

}