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Diffstat (limited to 'mpc/tests/random.c')
-rw-r--r-- | mpc/tests/random.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/mpc/tests/random.c b/mpc/tests/random.c new file mode 100644 index 0000000000..aa06355d3f --- /dev/null +++ b/mpc/tests/random.c @@ -0,0 +1,160 @@ +/* random.c -- Handle seed for random numbers. + +// Copyright (C) 2008, 2009, 2010, 2011 INRIA + +This file is part of GNU MPC. + +GNU MPC 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. + +GNU MPC 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 this program. If not, see http://www.gnu.org/licenses/ . +*/ + +/* Put test_start at the beginning of your test function and + test_end at the end. + These are an adaptation of those of MPFR. */ + +#include "config.h" +#include <stdlib.h> +#include "mpc-tests.h" + + +#ifdef TIME_WITH_SYS_TIME +# include <sys/time.h> +# include <time.h> +#else +# ifdef HAVE_SYS_TIME_H +# include <sys/time.h> +# else +# include <time.h> +# endif +#endif + +gmp_randstate_t rands; +static char rands_initialized; + +void +test_start (void) +{ + char *environment_seed; + unsigned long seed; + + if (rands_initialized) + { + fprintf (stderr, + "Put test_start at the beginning of your test function.\n"); + exit (1); + } + + gmp_randinit_default (rands); + rands_initialized = 1; + + environment_seed = getenv ("GMP_CHECK_RANDOMIZE"); + if (environment_seed == NULL) + gmp_randseed_ui (rands, 0xfac11e); + else + { + seed = (unsigned long int) atoi (environment_seed); + if (seed == 0 || seed == 1) + { +#if defined HAVE_GETTIMEOFDAY + struct timeval tv; + gettimeofday (&tv, NULL); + seed = (unsigned long int) (tv.tv_sec + tv.tv_usec); +#else + time_t tv; + time (&tv); + seed = (unsigned long int) tv; +#endif + gmp_randseed_ui (rands, seed); + printf ("Seed GMP_CHECK_RANDOMIZE=%lu " + "(include this in bug reports)\n", seed); + } + else + { + printf ("Re-seeding with GMP_CHECK_RANDOMIZE=%lu\n", seed); + gmp_randseed_ui (rands, seed); + } + } +} + +void +test_end (void) +{ + if (rands_initialized) + { + rands_initialized = 0; + gmp_randclear (rands); + } + mpfr_free_cache (); +} + +/* Set z to a non zero value random value with absolute values of Re(z) and + Im(z) either zero (but not both in the same time) or otherwise greater than + or equal to 2^{emin-1} and less than 2^emax. + Each part is negative with probability equal to NEGATIVE_PROBABILITY / 256. + The result has one zero part (but never the two of them) with probability + equal to ZERO_PROBABILITY / 256. +*/ +void +test_default_random (mpc_ptr z, mpfr_exp_t emin, mpfr_exp_t emax, + unsigned int negative_probability, + unsigned int zero_probability) +{ + const unsigned long range = (unsigned long int) (emax - emin) + 1; + unsigned long r; + + if (!rands_initialized) + { + fprintf (stderr, + "Put test_start at the beginning of your test function.\n"); + exit (1); + } + + do + { + mpc_urandom (z, rands); + } while (mpfr_zero_p (mpc_realref (z)) || mpfr_zero_p (mpc_imagref (z))); + + if (zero_probability > 256) + zero_probability = 256; + r = gmp_urandomb_ui (rands, 19); + if ((r & 0x1FF) < zero_probability + || ((r >> 9) & 0x1FF) < zero_probability) + { + int zero_re_p = (r & 0x1FF) < zero_probability; + int zero_im_p = ((r >> 9) & 0x1FF) < zero_probability; + + if (zero_re_p && zero_im_p) + { + /* we just want one zero part. */ + zero_re_p = (r >> 18) & 1; + zero_im_p = !zero_re_p; + } + if (zero_re_p) + mpfr_set_ui (mpc_realref (z), 0, GMP_RNDN); + if (zero_im_p) + mpfr_set_ui (mpc_imagref (z), 0, GMP_RNDN); + } + if (!mpfr_zero_p (mpc_realref (z))) + mpfr_set_exp (mpc_realref (z), (mpfr_exp_t) gmp_urandomm_ui (rands, range) + emin); + + if (!mpfr_zero_p (mpc_imagref (z))) + mpfr_set_exp (mpc_imagref (z), (mpfr_exp_t) gmp_urandomm_ui (rands, range) + emin); + + if (negative_probability > 256) + negative_probability = 256; + r = gmp_urandomb_ui (rands, 16); + if ((r & 0xFF) < negative_probability) + mpfr_neg (mpc_realref (z), mpc_realref (z), GMP_RNDN); + if (((r>>8) & 0xFF) < negative_probability) + mpfr_neg (mpc_imagref (z), mpc_imagref (z), GMP_RNDN); +} |