1 /* Test file for mpfr_pow.
2
3 Copyright 2001-2023 Free Software Foundation, Inc.
4 Contributed by the AriC and Caramba projects, INRIA.
5
6 This file is part of the GNU MPFR Library.
7
8 The GNU MPFR Library is free software; you can redistribute it and/or modify
9 it under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or (at your
11 option) any later version.
12
13 The GNU MPFR Library is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
16 License for more details.
17
18 You should have received a copy of the GNU Lesser General Public License
19 along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
20 https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
21 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
22
23 #include "mpfr-test.h"
24
25
26 int
main(int argc,char * argv[])27 main (int argc, char *argv[])
28 {
29 mpfr_t x, y, z;
30
31 mpfr_prec_t prec, yprec;
32 mpfr_t t, s;
33 mpfr_rnd_t rnd;
34 int inexact, compare, compare2;
35 unsigned int n, err;
36
37 mpfr_prec_t p0=2, p1=100;
38 unsigned int N=25;
39
40 tests_start_mpfr ();
41
42 mpfr_init (x);
43 mpfr_init2 (y,sizeof(unsigned long int)*CHAR_BIT);
44 mpfr_init (z);
45
46 mpfr_init (s);
47 mpfr_init (t);
48
49 /* generic test */
50 for (prec = p0; prec <= p1; prec++)
51 {
52 mpfr_set_prec (x, prec);
53 mpfr_set_prec (s, sizeof(unsigned long int)*CHAR_BIT);
54 mpfr_set_prec (z, prec);
55 mpfr_set_prec (t, prec);
56 yprec = prec + 10;
57
58 for (n=0; n<N; n++)
59 {
60 mpfr_urandomb (x, RANDS);
61 mpfr_urandomb (s, RANDS);
62 if (RAND_BOOL ())
63 mpfr_neg (s, s, MPFR_RNDN);
64 rnd = RND_RAND_NO_RNDF ();
65 mpfr_set_prec (y, yprec);
66 compare = mpfr_pow (y, x, s, rnd);
67 err = (rnd == MPFR_RNDN) ? yprec + 1 : yprec;
68 if (mpfr_can_round (y, err, rnd, rnd, prec))
69 {
70 mpfr_set (t, y, rnd);
71 inexact = mpfr_pow (z, x, s, rnd);
72 if (mpfr_cmp (t, z))
73 {
74 printf ("results differ for x^y with\n");
75 printf (" x=");
76 mpfr_dump (x);
77 printf (" y=");
78 mpfr_dump (s);
79 printf (" with prec=%u rnd_mode=%s\n", (unsigned int) prec,
80 mpfr_print_rnd_mode (rnd));
81 printf ("got ");
82 mpfr_dump (z);
83 printf ("expected ");
84 mpfr_dump (t);
85 printf ("approx ");
86 mpfr_dump (y);
87 exit (1);
88 }
89 compare2 = mpfr_cmp (t, y);
90 /* if rounding to nearest, cannot know the sign of t - f(x)
91 because of composed rounding: y = o(f(x)) and t = o(y) */
92 if ((rnd != MPFR_RNDN) && (compare * compare2 >= 0))
93 compare = compare + compare2;
94 else
95 compare = inexact; /* cannot determine sign(t-f(x)) */
96 if (((inexact == 0) && (compare != 0)) ||
97 ((inexact > 0) && (compare <= 0)) ||
98 ((inexact < 0) && (compare >= 0)))
99 {
100 printf ("Wrong inexact flag for rnd=%s: expected %d, got %d"
101 "\n", mpfr_print_rnd_mode (rnd), compare, inexact);
102 printf ("x="); mpfr_dump (x);
103 printf ("y="); mpfr_dump (y);
104 printf ("t="); mpfr_dump (t);
105 exit (1);
106 }
107 }
108 }
109 }
110
111 mpfr_clear (s);
112 mpfr_clear (t);
113
114 mpfr_clear (x);
115 mpfr_clear (y);
116 mpfr_clear (z);
117
118 tests_end_mpfr ();
119 return 0;
120 }
121