Mercurial > hg > octave-lojdl > gnulib-hg
annotate tests/test-frexp.c @ 9850:7f3ed6b093be
Guarantee a definition of NAN.
* lib/math.in.h (NAN): Define if missing.
* tests/test-math.c (main): Test it.
* doc/posix-headers/math.texi (math.h): Document this.
* lib/isnan.c (rpl_isnand): Use it.
* tests/test-ceilf1.c (NaN): Delete, and use NAN instead.
* tests/test-floorf1.c (NaN): Likewise.
* tests/test-frexp.c (NaN): Likewise.
* tests/test-isnand.c (NaN): Likewise.
* tests/test-isnanf.c (NaN): Likewise.
* tests/test-round1.c (NaN): Likewise.
* tests/test-roundf1.c (NaN): Likewise.
* tests/test-snprintf-posix.h (NaN): Likewise.
* tests/test-sprintf-posix.h (NaN): Likewise.
* tests/test-trunc1.c (NaN): Likewise.
* tests/test-truncf1.c (NaN): Likewise.
* tests/test-vasnprintf-posix.c (NaN): Likewise.
* tests/test-vasprintf-posix.c (NaN): Likewise.
* modules/isnand-nolibm (Depends-on): Add math.
* modules/isnanf-nolibm (Depends-on): Likewise.
* modules/isnanl (Depends-on): Likewise.
* modules/isnanl-nolibm (Depends-on): Likewise.
* modules/snprintf-posix-tests (Depends-on): Likewise.
* modules/sprintf-posix-tests (Depends-on): Likewise.
* modules/vsnprintf-posix-tests (Depends-on): Likewise.
* modules/vsprintf-posix-tests (Depends-on): Likewise.
* modules/vasnprintf-posix-tests (Depends-on): Likewise.
* modules/vasprintf-posix-tests (Depends-on): Likewise.
Signed-off-by: Eric Blake <ebb9@byu.net>
| author | Eric Blake <ebb9@byu.net> |
|---|---|
| date | Mon, 31 Mar 2008 20:56:25 -0600 |
| parents | a113e473cc98 |
| children | baba3b346ab2 |
| rev | line source |
|---|---|
| 8492 | 1 /* Test of splitting a double into fraction and mantissa. |
|
9646
a113e473cc98
Rename isnan, applicable to 'double' only, to isnand.
Bruno Haible <bruno@clisp.org>
parents:
9309
diff
changeset
|
2 Copyright (C) 2007-2008 Free Software Foundation, Inc. |
| 8492 | 3 |
|
9309
bbbbbf4cd1c5
Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents:
8754
diff
changeset
|
4 This program is free software: you can redistribute it and/or modify |
| 8492 | 5 it under the terms of the GNU General Public License as published by |
|
9309
bbbbbf4cd1c5
Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents:
8754
diff
changeset
|
6 the Free Software Foundation; either version 3 of the License, or |
|
bbbbbf4cd1c5
Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents:
8754
diff
changeset
|
7 (at your option) any later version. |
| 8492 | 8 |
| 9 This program is distributed in the hope that it will be useful, | |
| 10 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 12 GNU General Public License for more details. | |
| 13 | |
| 14 You should have received a copy of the GNU General Public License | |
|
9309
bbbbbf4cd1c5
Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents:
8754
diff
changeset
|
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 8492 | 16 |
| 17 /* Written by Bruno Haible <bruno@clisp.org>, 2007. */ | |
| 18 | |
| 19 #include <config.h> | |
| 20 | |
| 21 #include <math.h> | |
| 22 | |
| 23 #include <float.h> | |
| 8754 | 24 #include <stdio.h> |
| 8492 | 25 #include <stdlib.h> |
| 26 | |
|
9646
a113e473cc98
Rename isnan, applicable to 'double' only, to isnand.
Bruno Haible <bruno@clisp.org>
parents:
9309
diff
changeset
|
27 #include "isnand.h" |
|
8545
418f381347dc
Work around IRIX 6.5 cc compiler bug, which simplifies x != x to false.
Bruno Haible <bruno@clisp.org>
parents:
8543
diff
changeset
|
28 |
| 8754 | 29 #define ASSERT(expr) \ |
| 30 do \ | |
| 31 { \ | |
| 32 if (!(expr)) \ | |
| 33 { \ | |
| 34 fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \ | |
| 35 abort (); \ | |
| 36 } \ | |
| 37 } \ | |
| 38 while (0) | |
| 8492 | 39 |
| 40 static double | |
| 41 my_ldexp (double x, int d) | |
| 42 { | |
| 43 for (; d > 0; d--) | |
| 44 x *= 2.0; | |
| 45 for (; d < 0; d++) | |
| 46 x *= 0.5; | |
| 47 return x; | |
| 48 } | |
| 49 | |
| 50 int | |
| 51 main () | |
| 52 { | |
| 53 int i; | |
| 54 /* The use of 'volatile' guarantees that excess precision bits are dropped | |
| 55 when dealing with denormalized numbers. It is necessary on x86 systems | |
| 56 where double-floats are not IEEE compliant by default, to avoid that the | |
| 57 results become platform and compiler option dependent. 'volatile' is a | |
| 58 portable alternative to gcc's -ffloat-store option. */ | |
| 59 volatile double x; | |
| 60 | |
| 61 { /* NaN. */ | |
| 62 int exp = -9999; | |
| 63 double mantissa; | |
| 9850 | 64 x = NAN; |
| 8492 | 65 mantissa = frexp (x, &exp); |
|
9646
a113e473cc98
Rename isnan, applicable to 'double' only, to isnand.
Bruno Haible <bruno@clisp.org>
parents:
9309
diff
changeset
|
66 ASSERT (isnand (mantissa)); |
| 8492 | 67 } |
| 68 | |
| 69 { /* Positive infinity. */ | |
| 70 int exp = -9999; | |
| 71 double mantissa; | |
| 72 x = 1.0 / 0.0; | |
| 73 mantissa = frexp (x, &exp); | |
| 74 ASSERT (mantissa == x); | |
| 75 } | |
| 76 | |
| 77 { /* Negative infinity. */ | |
| 78 int exp = -9999; | |
| 79 double mantissa; | |
| 80 x = -1.0 / 0.0; | |
| 81 mantissa = frexp (x, &exp); | |
| 82 ASSERT (mantissa == x); | |
| 83 } | |
| 84 | |
| 85 { /* Positive zero. */ | |
| 86 int exp = -9999; | |
| 87 double mantissa; | |
| 88 x = 0.0; | |
| 89 mantissa = frexp (x, &exp); | |
| 90 ASSERT (exp == 0); | |
| 91 ASSERT (mantissa == x); | |
|
8654
a2bc90a7b7aa
Test also the sign bit of zero results.
Bruno Haible <bruno@clisp.org>
parents:
8545
diff
changeset
|
92 ASSERT (!signbit (mantissa)); |
| 8492 | 93 } |
| 94 | |
| 95 { /* Negative zero. */ | |
| 96 int exp = -9999; | |
| 97 double mantissa; | |
| 98 x = -0.0; | |
| 99 mantissa = frexp (x, &exp); | |
| 100 ASSERT (exp == 0); | |
| 101 ASSERT (mantissa == x); | |
|
8654
a2bc90a7b7aa
Test also the sign bit of zero results.
Bruno Haible <bruno@clisp.org>
parents:
8545
diff
changeset
|
102 ASSERT (signbit (mantissa)); |
| 8492 | 103 } |
| 104 | |
| 105 for (i = 1, x = 1.0; i <= DBL_MAX_EXP; i++, x *= 2.0) | |
| 106 { | |
| 107 int exp = -9999; | |
| 108 double mantissa = frexp (x, &exp); | |
| 109 ASSERT (exp == i); | |
| 110 ASSERT (mantissa == 0.5); | |
| 111 } | |
| 112 for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5) | |
| 113 { | |
| 114 int exp = -9999; | |
| 115 double mantissa = frexp (x, &exp); | |
| 116 ASSERT (exp == i); | |
| 117 ASSERT (mantissa == 0.5); | |
| 118 } | |
| 119 for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) | |
| 120 { | |
| 121 int exp = -9999; | |
| 122 double mantissa = frexp (x, &exp); | |
| 123 ASSERT (exp == i); | |
| 124 ASSERT (mantissa == 0.5); | |
| 125 } | |
| 126 | |
| 127 for (i = 1, x = -1.0; i <= DBL_MAX_EXP; i++, x *= 2.0) | |
| 128 { | |
| 129 int exp = -9999; | |
| 130 double mantissa = frexp (x, &exp); | |
| 131 ASSERT (exp == i); | |
| 132 ASSERT (mantissa == -0.5); | |
| 133 } | |
| 134 for (i = 1, x = -1.0; i >= DBL_MIN_EXP; i--, x *= 0.5) | |
| 135 { | |
| 136 int exp = -9999; | |
| 137 double mantissa = frexp (x, &exp); | |
| 138 ASSERT (exp == i); | |
| 139 ASSERT (mantissa == -0.5); | |
| 140 } | |
| 141 for (; i >= DBL_MIN_EXP - 100 && x < 0.0; i--, x *= 0.5) | |
| 142 { | |
| 143 int exp = -9999; | |
| 144 double mantissa = frexp (x, &exp); | |
| 145 ASSERT (exp == i); | |
| 146 ASSERT (mantissa == -0.5); | |
| 147 } | |
| 148 | |
| 149 for (i = 1, x = 1.01; i <= DBL_MAX_EXP; i++, x *= 2.0) | |
| 150 { | |
| 151 int exp = -9999; | |
| 152 double mantissa = frexp (x, &exp); | |
| 153 ASSERT (exp == i); | |
| 154 ASSERT (mantissa == 0.505); | |
| 155 } | |
| 156 for (i = 1, x = 1.01; i >= DBL_MIN_EXP; i--, x *= 0.5) | |
| 157 { | |
| 158 int exp = -9999; | |
| 159 double mantissa = frexp (x, &exp); | |
| 160 ASSERT (exp == i); | |
| 161 ASSERT (mantissa == 0.505); | |
| 162 } | |
| 163 for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) | |
| 164 { | |
| 165 int exp = -9999; | |
| 166 double mantissa = frexp (x, &exp); | |
| 167 ASSERT (exp == i); | |
| 168 ASSERT (mantissa >= 0.5); | |
| 169 ASSERT (mantissa < 1.0); | |
| 170 ASSERT (mantissa == my_ldexp (x, - exp)); | |
| 171 } | |
| 172 | |
| 173 for (i = 1, x = 1.73205; i <= DBL_MAX_EXP; i++, x *= 2.0) | |
| 174 { | |
| 175 int exp = -9999; | |
| 176 double mantissa = frexp (x, &exp); | |
| 177 ASSERT (exp == i); | |
| 178 ASSERT (mantissa == 0.866025); | |
| 179 } | |
| 180 for (i = 1, x = 1.73205; i >= DBL_MIN_EXP; i--, x *= 0.5) | |
| 181 { | |
| 182 int exp = -9999; | |
| 183 double mantissa = frexp (x, &exp); | |
| 184 ASSERT (exp == i); | |
| 185 ASSERT (mantissa == 0.866025); | |
| 186 } | |
| 187 for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) | |
| 188 { | |
| 189 int exp = -9999; | |
| 190 double mantissa = frexp (x, &exp); | |
| 191 ASSERT (exp == i || exp == i + 1); | |
| 192 ASSERT (mantissa >= 0.5); | |
| 193 ASSERT (mantissa < 1.0); | |
| 194 ASSERT (mantissa == my_ldexp (x, - exp)); | |
| 195 } | |
| 196 | |
| 197 return 0; | |
| 198 } |