tests/rand-test.c

   1 #undef G_DISABLE_ASSERT
   2 #undef G_LOG_DOMAIN
   3
   4 #include <glib.h>
   5
   6 /* Outputs tested against the reference implementation mt19937ar.c from
   7    http://www.math.keio.ac.jp/~matumoto/MT2002/emt19937ar.html */
   8
   9 /* Tests for a simple seed, first number is the seed */
  10 const guint32 first_numbers[] =
  11 {
  12   0x7a7a7a7a,
  13   0xfdcc2d54,
  14   0x3a279ceb,
  15   0xc4d39c33,
  16   0xf31895cd,
  17   0x46ca0afc,
  18   0x3f5484ff,
  19   0x54bc9557,
  20   0xed2c24b1,
  21   0x84062503,
  22   0x8f6404b3,
  23   0x599a94b3,
  24   0xe46d03d5,
  25   0x310beb78,
  26   0x7bee5d08,
  27   0x760d09be,
  28   0x59b6e163,
  29   0xbf6d16ec,
  30   0xcca5fb54,
  31   0x5de7259b,
  32   0x1696330c,
  33 };
  34
  35 /* array seed */
  36 const guint32 seed_array[] =
  37 {
  38   0x6553375f,
  39   0xd6b8d43b,
  40   0xa1e7667f,
  41   0x2b10117c
  42 };
  43
  44 /* tests for the array seed */
  45 const guint32 array_outputs[] =
  46 {
  47   0xc22b7dc3,
  48   0xfdecb8ae,
  49   0xb4af0738,
  50   0x516bc6e1,
  51   0x7e372e91,
  52   0x2d38ff80,
  53   0x6096494a,
  54   0xd162d5a8,
  55   0x3c0aaa0d,
  56   0x10e736ae
  57 };
  58
  59 const gint length = sizeof (first_numbers) / sizeof (first_numbers[0]);
  60 const gint seed_length = sizeof (seed_array) / sizeof (seed_array[0]);
  61 const gint array_length = sizeof (array_outputs) / sizeof (array_outputs[0]);
  62
  63 int main()
  64 {
  65   guint n;
  66   guint ones;
  67   double proportion;
  68
  69   GRand* rand = g_rand_new_with_seed (first_numbers[0]);
  70   GRand* copy;
  71
  72   for (n = 1; n < length; n++)
  73     g_assert (first_numbers[n] == g_rand_int (rand));
  74
  75   g_rand_set_seed (rand, 2);
  76   g_rand_set_seed_array (rand, seed_array, seed_length);
  77
  78   for (n = 0; n < array_length; n++)
  79     g_assert (array_outputs[n] == g_rand_int (rand));
  80
  81   copy = g_rand_copy (rand);
  82   for (n = 0; n < 100; n++)
  83     g_assert (g_rand_int (copy) == g_rand_int (rand));
  84
  85   for (n = 1; n < 100000; n++)
  86     {
  87       gint32 i;
  88       gdouble d;
  89       gboolean b;
  90
  91       i = g_rand_int_range (rand, 8,16);
  92       g_assert (i >= 8 && i < 16);
  93
  94       i = g_random_int_range (8,16);
  95       g_assert (i >= 8 && i < 16);
  96
  97       d = g_rand_double (rand);
  98       g_assert (d >= 0 && d < 1);
  99
 100       d = g_random_double ();
 101       g_assert (d >= 0 && d < 1);
 102
 103       d = g_rand_double_range (rand, -8, 32);
 104       g_assert (d >= -8 && d < 32);
 105
 106       d = g_random_double_range (-8, 32);
 107       g_assert (d >= -8 && d < 32);
 108
 109       b = g_random_boolean ();
 110       g_assert (b == TRUE || b  == FALSE);
 111
 112       b = g_rand_boolean (rand);
 113       g_assert (b == TRUE || b  == FALSE);
 114     }
 115
 116   /* Statistical sanity check, count the number of ones
 117    * when getting random numbers in range [0,3) and see
 118    * that it must be semi-close to 0.25 with a VERY large
 119    * probability */
 120   ones = 0;
 121   for (n = 1; n < 100000; n++)
 122     {
 123       if (g_random_int_range (0, 4) == 1)
 124         ones ++;
 125     }
 126   proportion = (double)ones / (double)100000;
 127   /* 0.025 is overkill, but should suffice to test for some unreasonability */
 128   g_assert (ABS (proportion - 0.25) < 0.025);
 129
 130   g_rand_free (rand);
 131   g_rand_free (copy);
 132
 133   return 0;
 134 }
 135