diff options
Diffstat (limited to 'gmp-6.3.0/tests/mpq/t-get_d.c')
| -rw-r--r-- | gmp-6.3.0/tests/mpq/t-get_d.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/gmp-6.3.0/tests/mpq/t-get_d.c b/gmp-6.3.0/tests/mpq/t-get_d.c new file mode 100644 index 0000000..98d6a5f --- /dev/null +++ b/gmp-6.3.0/tests/mpq/t-get_d.c @@ -0,0 +1,294 @@ +/* Test mpq_get_d and mpq_set_d + +Copyright 1991, 1993, 1994, 1996, 2000-2003, 2012, 2013 Free Software +Foundation, Inc. + +This file is part of the GNU MP Library test suite. + +The GNU MP Library test suite is free software; you can redistribute it +and/or modify it under the terms of the GNU 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 MP Library test suite 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 General +Public License for more details. + +You should have received a copy of the GNU General Public License along with +the GNU MP Library test suite. If not, see https://www.gnu.org/licenses/. */ + +#include <stdio.h> +#include <stdlib.h> + +#include "gmp-impl.h" +#include "tests.h" + +#ifndef SIZE +#define SIZE 8 +#endif + +/* VAX D floats only have an 8 bit signed exponent, so anything 2^128 or + bigger will overflow, that being 4 limbs. */ +#if defined (__vax) || defined (__vax__) && SIZE > 4 +#undef SIZE +#define SIZE 4 +#define EPSIZE 3 +#else +#define EPSIZE SIZE +#endif + +void dump (mpq_t); + +void +check_monotonic (int argc, char **argv) +{ + mpq_t a; + mp_size_t size; + int reps = 100; + int i, j; + double last_d, new_d; + mpq_t qlast_d, qnew_d; + mpq_t eps; + + if (argc == 2) + reps = atoi (argv[1]); + + /* The idea here is to test the monotonousness of mpq_get_d by adding + numbers to the numerator and denominator. */ + + mpq_init (a); + mpq_init (eps); + mpq_init (qlast_d); + mpq_init (qnew_d); + + for (i = 0; i < reps; i++) + { + size = urandom () % SIZE - SIZE/2; + mpz_random2 (mpq_numref (a), size); + do + { + size = urandom () % SIZE - SIZE/2; + mpz_random2 (mpq_denref (a), size); + } + while (mpz_cmp_ui (mpq_denref (a), 0) == 0); + + mpq_canonicalize (a); + + last_d = mpq_get_d (a); + mpq_set_d (qlast_d, last_d); + for (j = 0; j < 10; j++) + { + size = urandom () % EPSIZE + 1; + mpz_random2 (mpq_numref (eps), size); + size = urandom () % EPSIZE + 1; + mpz_random2 (mpq_denref (eps), size); + mpq_canonicalize (eps); + + mpq_add (a, a, eps); + mpq_canonicalize (a); + new_d = mpq_get_d (a); + if (last_d > new_d) + { + printf ("\nERROR (test %d/%d): bad mpq_get_d results\n", i, j); + printf ("last: %.16g\n", last_d); + printf (" new: %.16g\n", new_d); dump (a); + abort (); + } + mpq_set_d (qnew_d, new_d); + MPQ_CHECK_FORMAT (qnew_d); + if (mpq_cmp (qlast_d, qnew_d) > 0) + { + printf ("ERROR (test %d/%d): bad mpq_set_d results\n", i, j); + printf ("last: %.16g\n", last_d); dump (qlast_d); + printf (" new: %.16g\n", new_d); dump (qnew_d); + abort (); + } + last_d = new_d; + mpq_set (qlast_d, qnew_d); + } + } + + mpq_clear (a); + mpq_clear (eps); + mpq_clear (qlast_d); + mpq_clear (qnew_d); +} + +double +my_ldexp (double d, int e) +{ + for (;;) + { + if (e > 0) + { + if (e >= 16) + { + d *= 65536.0; + e -= 16; + } + else + { + d *= 2.0; + e -= 1; + } + } + else if (e < 0) + { + + if (e <= -16) + { + d /= 65536.0; + e += 16; + } + else + { + d /= 2.0; + e += 1; + } + } + else + return d; + } +} + +#define MAXEXP 500 + +#if defined (__vax) || defined (__vax__) +#undef MAXEXP +#define MAXEXP 30 +#endif + +void +check_random (int argc, char **argv) +{ + gmp_randstate_ptr rands = RANDS; + + double d; + mpq_t q; + mpz_t a, t; + int exp; + + int test, reps = 100000; + + if (argc == 2) + reps = 100 * atoi (argv[1]); + + mpq_init (q); + mpz_init (a); + mpz_init (t); + + for (test = 0; test < reps; test++) + { + mpz_rrandomb (a, rands, 53); + mpz_urandomb (t, rands, 32); + exp = mpz_get_ui (t) % (2*MAXEXP) - MAXEXP; + + d = my_ldexp (mpz_get_d (a), exp); + mpq_set_d (q, d); + /* Check that n/d = a * 2^exp, or + d*a 2^{exp} = n */ + mpz_mul (t, a, mpq_denref (q)); + if (exp > 0) + mpz_mul_2exp (t, t, exp); + else + { + if (!mpz_divisible_2exp_p (t, -exp)) + goto fail; + mpz_div_2exp (t, t, -exp); + } + if (mpz_cmp (t, mpq_numref (q)) != 0) + { + fail: + printf ("ERROR (check_random test %d): bad mpq_set_d results\n", test); + printf ("%.16g\n", d); + gmp_printf ("%Qd\n", q); + abort (); + } + } + mpq_clear (q); + mpz_clear (t); + mpz_clear (a); +} + +void +dump (mpq_t x) +{ + mpz_out_str (stdout, 10, mpq_numref (x)); + printf ("/"); + mpz_out_str (stdout, 10, mpq_denref (x)); + printf ("\n"); +} + +/* Check various values 2^n and 1/2^n. */ +void +check_onebit (void) +{ + static const long data[] = { + -3*GMP_NUMB_BITS-1, -3*GMP_NUMB_BITS, -3*GMP_NUMB_BITS+1, + -2*GMP_NUMB_BITS-1, -2*GMP_NUMB_BITS, -2*GMP_NUMB_BITS+1, + -GMP_NUMB_BITS-1, -GMP_NUMB_BITS, -GMP_NUMB_BITS+1, + -5, -2, -1, 0, 1, 2, 5, + GMP_NUMB_BITS-1, GMP_NUMB_BITS, GMP_NUMB_BITS+1, + 2*GMP_NUMB_BITS-1, 2*GMP_NUMB_BITS, 2*GMP_NUMB_BITS+1, + 3*GMP_NUMB_BITS-1, 3*GMP_NUMB_BITS, 3*GMP_NUMB_BITS+1, + }; + + int i, neg; + long exp, l; + mpq_t q; + double got, want; + + mpq_init (q); + + for (i = 0; i < numberof (data); i++) + { + exp = data[i]; + + mpq_set_ui (q, 1L, 1L); + if (exp >= 0) + mpq_mul_2exp (q, q, exp); + else + mpq_div_2exp (q, q, -exp); + + want = 1.0; + for (l = 0; l < exp; l++) + want *= 2.0; + for (l = 0; l > exp; l--) + want /= 2.0; + + for (neg = 0; neg <= 1; neg++) + { + if (neg) + { + mpq_neg (q, q); + want = -want; + } + + got = mpq_get_d (q); + + if (got != want) + { + printf ("mpq_get_d wrong on %s2**%ld\n", neg ? "-" : "", exp); + mpq_trace (" q ", q); + d_trace (" want ", want); + d_trace (" got ", got); + abort(); + } + } + } + mpq_clear (q); +} + +int +main (int argc, char **argv) +{ + tests_start (); + + check_onebit (); + check_monotonic (argc, argv); + check_random (argc, argv); + + tests_end (); + exit (0); +} |