1 /* Test mpf_sqrt_ui. 2 3 Copyright 2004, 2015 Free Software Foundation, Inc. 4 5 This file is part of the GNU MP Library test suite. 6 7 The GNU MP Library test suite is free software; you can redistribute it 8 and/or modify it under the terms of the GNU General Public License as 9 published by the Free Software Foundation; either version 3 of the License, 10 or (at your option) any later version. 11 12 The GNU MP Library test suite is distributed in the hope that it will be 13 useful, but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 15 Public License for more details. 16 17 You should have received a copy of the GNU General Public License along with 18 the GNU MP Library test suite. If not, see https://www.gnu.org/licenses/. */ 19 20 #include <stdio.h> 21 #include <stdlib.h> 22 23 #include "gmp.h" 24 #include "gmp-impl.h" 25 #include "tests.h" 26 27 28 void 29 check_rand (void) 30 { 31 unsigned long max_prec = 15; 32 unsigned long min_prec = __GMPF_BITS_TO_PREC (1); 33 gmp_randstate_ptr rands = RANDS; 34 unsigned long x, prec; 35 mpf_t r, s; 36 int i; 37 38 mpf_init (r); 39 mpf_init (s); 40 refmpf_set_prec_limbs (s, 2*max_prec+10); 41 42 for (x = 0; x < 2; x++) 43 { 44 mpf_sqrt_ui (r, x); 45 MPF_CHECK_FORMAT (r); 46 if (mpf_cmp_ui (r, x) != 0) 47 { 48 printf ("mpf_sqrt_ui wrong for special case:\n"); 49 printf (" x=%lu\n", x); 50 mpf_trace (" r", r); 51 abort (); 52 } 53 } 54 55 for (i = 0; i < 50; i++) 56 { 57 /* input, a random non-zero ulong, exponentially distributed */ 58 do { 59 x = gmp_urandomb_ui (rands, 60 gmp_urandomm_ui (rands, BITS_PER_ULONG) + 1); 61 } while (x <= 1); 62 63 /* result precision */ 64 prec = gmp_urandomm_ui (rands, max_prec-min_prec) + min_prec; 65 refmpf_set_prec_limbs (r, prec); 66 67 mpf_sqrt_ui (r, x); 68 MPF_CHECK_FORMAT (r); 69 70 /* Expect to prec limbs of result. 71 In the current implementation there's no stripping of low zero 72 limbs in mpf_sqrt_ui, not even on perfect squares, so size should 73 be exactly prec. */ 74 if (SIZ(r) != prec) 75 { 76 printf ("mpf_sqrt_ui result not enough result limbs\n"); 77 printf (" x=%lu\n", x); 78 printf (" want prec=%lu\n", prec); 79 mpf_trace (" r", r); 80 printf (" r size %ld\n", (long) SIZ(r)); 81 printf (" r prec %ld\n", (long) PREC(r)); 82 abort (); 83 } 84 85 /* Must have r^2 <= x, since r has been truncated. */ 86 mpf_mul (s, r, r); 87 if (! (mpf_cmp_ui (s, x) <= 0)) 88 { 89 printf ("mpf_sqrt_ui result too big\n"); 90 printf (" x=%lu\n", x); 91 printf (" want prec=%lu\n", prec); 92 mpf_trace (" r", r); 93 mpf_trace (" s", s); 94 abort (); 95 } 96 97 /* Must have (r+ulp)^2 > x. 98 No overflow from refmpf_add_ulp since r is only prec limbs. */ 99 refmpf_add_ulp (r); 100 mpf_mul (s, r, r); 101 if (! (mpf_cmp_ui (s, x) > 0)) 102 { 103 printf ("mpf_sqrt_ui result too small\n"); 104 printf (" x=%lu\n", x); 105 printf (" want prec=%lu\n", prec); 106 mpf_trace (" r+ulp", r); 107 mpf_trace (" s", s); 108 abort (); 109 } 110 } 111 112 mpf_clear (r); 113 mpf_clear (s); 114 } 115 116 int 117 main (int argc, char **argv) 118 { 119 tests_start (); 120 mp_trace_base = -16; 121 122 check_rand (); 123 124 tests_end (); 125 exit (0); 126 } 127