1 /* Test file for mpfr_log.
2
3 Copyright 1999, 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 #ifdef CHECK_EXTERNAL
26 static int
27 test_log (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode)
28 {
29 int res;
30 int ok = rnd_mode == MPFR_RNDN && mpfr_number_p (b) && mpfr_get_prec (a)>=53;
31 if (ok)
32 {
33 mpfr_print_raw (b);
34 }
35 res = mpfr_log (a, b, rnd_mode);
36 if (ok)
37 {
38 printf (" ");
39 mpfr_print_raw (a);
40 printf ("\n");
41 }
42 return res;
43 }
44 #else
45 #define test_log mpfr_log
46 #endif
47
48 static void
49 check2 (const char *as, mpfr_rnd_t rnd_mode, const char *res1s)
50 {
51 mpfr_t ta, tres;
52
53 mpfr_inits2 (53, ta, tres, (mpfr_ptr) 0);
54 mpfr_set_str1 (ta, as);
55 test_log (tres, ta, rnd_mode);
56
57 if (mpfr_cmp_str1 (tres, res1s))
58 {
59 printf ("mpfr_log failed for a=%s, rnd_mode=%s\n",
60 as, mpfr_print_rnd_mode (rnd_mode));
61 printf ("correct result is %s\n mpfr_log gives ",
62 res1s);
63 mpfr_out_str(stdout, 10, 0, tres, MPFR_RNDN);
64 printf ("\n");
65 exit (1);
66 }
67 mpfr_clears (ta, tres, (mpfr_ptr) 0);
68 }
69
70 static void
71 check3 (char *s, unsigned long prec, mpfr_rnd_t rnd)
72 {
73 mpfr_t x, y;
74
75 mpfr_init2 (x, prec);
76 mpfr_init2 (y, prec);
77 mpfr_set_str (x, s, 10, rnd);
78 test_log (y, x, rnd);
79 mpfr_out_str (stdout, 10, 0, y, rnd);
80 puts ("");
81 mpfr_clear (x);
82 mpfr_clear (y);
83 }
84
85 /* examples from Jean-Michel Muller and Vincent Lefevre
86 Cf http://perso.ens-lyon.fr/jean-michel.muller/Intro-to-TMD.htm
87 */
88
89 static void
90 check_worst_cases (void)
91 {
92 check2("1.00089971802309629645", MPFR_RNDD, "8.99313519443722736088e-04");
93 check2("1.00089971802309629645", MPFR_RNDN, "8.99313519443722844508e-04");
94 check2("1.00089971802309629645", MPFR_RNDU, "8.99313519443722844508e-04");
95
96 check2("1.01979300812244555452", MPFR_RNDD, "1.95996734891603630047e-02");
97 check2("1.01979300812244555452", MPFR_RNDN, "1.95996734891603664741e-02");
98 check2("1.01979300812244555452", MPFR_RNDU, "1.95996734891603664741e-02");
99
100 check2("1.02900871924604464525", MPFR_RNDD, "2.85959303301472726744e-02");
101 check2("1.02900871924604464525", MPFR_RNDN, "2.85959303301472761438e-02");
102 check2("1.02900871924604464525", MPFR_RNDU, "2.85959303301472761438e-02");
103
104 check2("1.27832870030418943585", MPFR_RNDD, "2.45553521871417795852e-01");
105 check2("1.27832870030418943585", MPFR_RNDN, "2.45553521871417823608e-01");
106 check2("1.27832870030418943585", MPFR_RNDU, "2.45553521871417823608e-01");
107
108 check2("1.31706530746788241792", MPFR_RNDD, "2.75406009586277422674e-01");
109 check2("1.31706530746788241792", MPFR_RNDN, "2.75406009586277478185e-01");
110 check2("1.31706530746788241792", MPFR_RNDU, "2.75406009586277478185e-01");
111
112 check2("1.47116981099449883885", MPFR_RNDD, "3.86057874110010412760e-01");
113 check2("1.47116981099449883885", MPFR_RNDN, "3.86057874110010412760e-01");
114 check2("1.47116981099449883885", MPFR_RNDU, "3.86057874110010468272e-01");
115
116 check2("1.58405446812987782401", MPFR_RNDD, "4.59987679246663727639e-01");
117 check2("1.58405446812987782401", MPFR_RNDN, "4.59987679246663783150e-01");
118 check2("1.58405446812987782401", MPFR_RNDU, "4.59987679246663783150e-01");
119
120 check2("1.67192331263391547047", MPFR_RNDD, "5.13974647961076613889e-01");
121 check2("1.67192331263391547047", MPFR_RNDN, "5.13974647961076724911e-01");
122 check2("1.67192331263391547047", MPFR_RNDU, "5.13974647961076724911e-01");
123
124 check2("1.71101198068990645318", MPFR_RNDD, "5.37084997042120315669e-01");
125 check2("1.71101198068990645318", MPFR_RNDN, "5.37084997042120315669e-01");
126 check2("1.71101198068990645318", MPFR_RNDU, "5.37084997042120426691e-01");
127
128 check2("1.72634853551388700588", MPFR_RNDD, "5.46008504786553605648e-01");
129 check2("1.72634853551388700588", MPFR_RNDN, "5.46008504786553716670e-01");
130 check2("1.72634853551388700588", MPFR_RNDU, "5.46008504786553716670e-01");
131
132 check2("2.00028876593004323325", MPFR_RNDD, "6.93291553102749702475e-01");
133 check2("2.00028876593004323325", MPFR_RNDN, "6.93291553102749813497e-01");
134 check2("2.00028876593004323325", MPFR_RNDU, "6.93291553102749813497e-01");
135
136 check2("6.27593230200363105808", MPFR_RNDD, "1.83672204800630312072");
137 check2("6.27593230200363105808", MPFR_RNDN, "1.83672204800630334276");
138 check2("6.27593230200363105808", MPFR_RNDU, "1.83672204800630334276");
139
140 check2("7.47216682321367997588", MPFR_RNDD, "2.01118502712453661729");
141 check2("7.47216682321367997588", MPFR_RNDN, "2.01118502712453706138");
142 check2("7.47216682321367997588", MPFR_RNDU, "2.01118502712453706138");
143
144 check2("9.34589857718275318632", MPFR_RNDD, "2.23493759221664944903");
145 check2("9.34589857718275318632", MPFR_RNDN, "2.23493759221664989312");
146 check2("9.34589857718275318632", MPFR_RNDU, "2.23493759221664989312");
147
148 check2("10.6856587560831854944", MPFR_RNDD, "2.36890253928838445674");
149 check2("10.6856587560831854944", MPFR_RNDN, "2.36890253928838445674");
150 check2("10.6856587560831854944", MPFR_RNDU, "2.36890253928838490083");
151
152 check2("12.4646345033981766903", MPFR_RNDD, "2.52289539471636015122");
153 check2("12.4646345033981766903", MPFR_RNDN, "2.52289539471636015122");
154 check2("12.4646345033981766903", MPFR_RNDU, "2.52289539471636059531");
155
156 check2("17.0953275851761752335", MPFR_RNDD, "2.83880518553861849185");
157 check2("17.0953275851761752335", MPFR_RNDN, "2.83880518553861893594");
158 check2("17.0953275851761752335", MPFR_RNDU, "2.83880518553861893594");
159
160 check2("19.8509496207496916043", MPFR_RNDD, "2.98825184582516722998");
161 check2("19.8509496207496916043", MPFR_RNDN, "2.98825184582516722998");
162 check2("19.8509496207496916043", MPFR_RNDU, "2.98825184582516767406");
163
164 check2("23.9512076062771335216", MPFR_RNDD, "3.17601874455977206679");
165 check2("23.9512076062771335216", MPFR_RNDN, "3.17601874455977206679");
166 check2("23.9512076062771335216", MPFR_RNDU, "3.17601874455977251088");
167
168 check2("428.315247165198229595", MPFR_RNDD, "6.05985948325268264369");
169 check2("428.315247165198229595", MPFR_RNDN, "6.05985948325268353187");
170 check2("428.315247165198229595", MPFR_RNDU, "6.05985948325268353187");
171 }
172
173 static void
174 special (void)
175 {
176 mpfr_t x, y;
177 int inex;
178 mpfr_exp_t emin, emax;
179 int r;
180
181 emin = mpfr_get_emin ();
182 emax = mpfr_get_emax ();
183
184 mpfr_init2 (x, 53);
185 mpfr_init2 (y, 53);
186
187 /* Check special case: An overflow in const_pi could occurs! */
188 set_emin (-125);
189 set_emax (128);
190 mpfr_set_prec (y, 24*2);
191 mpfr_set_prec (x, 24);
192 mpfr_set_str_binary (x, "0.111110101010101011110101E0");
193 test_log (y, x, MPFR_RNDN);
194 set_emin (emin);
195 set_emax (emax);
196
197 mpfr_set_prec (y, 53);
198 mpfr_set_prec (x, 53);
199 mpfr_set_ui (x, 3, MPFR_RNDD);
200 test_log (y, x, MPFR_RNDD);
201 if (mpfr_cmp_str1 (y, "1.09861228866810956"))
202 {
203 printf ("Error in mpfr_log(3) for MPFR_RNDD\n");
204 exit (1);
205 }
206
207 /* check large precision */
208 mpfr_set_prec (x, 3322);
209 mpfr_set_prec (y, 3322);
210 mpfr_set_ui (x, 3, MPFR_RNDN);
211 mpfr_sqrt (x, x, MPFR_RNDN);
212 test_log (y, x, MPFR_RNDN);
213
214 /* negative argument */
215 mpfr_set_si (x, -1, MPFR_RNDN);
216 test_log (y, x, MPFR_RNDN);
217 MPFR_ASSERTN(mpfr_nan_p (y));
218
219 /* infinite loop when */
220 set_emax (128);
221 mpfr_set_prec (x, 251);
222 mpfr_set_prec (y, 251);
223 mpfr_set_str_binary (x, "0.10010111000000000001101E8");
224 /* x = 4947981/32768, log(x) ~ 5.017282... */
225 test_log (y, x, MPFR_RNDN);
226
227 set_emax (emax);
228
229 mpfr_set_ui (x, 0, MPFR_RNDN);
230 inex = test_log (y, x, MPFR_RNDN);
231 MPFR_ASSERTN (inex == 0);
232 MPFR_ASSERTN (mpfr_inf_p (y));
233 MPFR_ASSERTN (mpfr_sgn (y) < 0);
234
235 mpfr_set_ui (x, 0, MPFR_RNDN);
236 mpfr_neg (x, x, MPFR_RNDN);
237 inex = test_log (y, x, MPFR_RNDN);
238 MPFR_ASSERTN (inex == 0);
239 MPFR_ASSERTN (mpfr_inf_p (y));
240 MPFR_ASSERTN (mpfr_sgn (y) < 0);
241
242 /* check log(1) is +0 whatever the rounding mode */
243 mpfr_set_ui (x, 1, MPFR_RNDN);
244 RND_LOOP (r)
245 {
246 mpfr_clear_flags ();
247 inex = test_log (y, x, (mpfr_rnd_t) r);
248 MPFR_ASSERTN (__gmpfr_flags == 0);
249 MPFR_ASSERTN (inex == 0);
250 MPFR_ASSERTN (MPFR_IS_ZERO (y));
251 MPFR_ASSERTN (MPFR_IS_POS (y));
252 }
253
254 mpfr_clear (x);
255 mpfr_clear (y);
256 }
257
258 static void
259 x_near_one (void)
260 {
261 mpfr_t x, y;
262 int inex;
263
264 mpfr_init2 (x, 32);
265 mpfr_init2 (y, 16);
266
267 mpfr_set_ui (x, 1, MPFR_RNDN);
268 mpfr_nextbelow (x);
269 inex = mpfr_log (y, x, MPFR_RNDD);
270 if (mpfr_cmp_str (y, "-0.1000000000000001E-31", 2, MPFR_RNDN)
271 || inex >= 0)
272 {
273 printf ("Failure in x_near_one, got inex = %d and\ny = ", inex);
274 mpfr_dump (y);
275 }
276
277 mpfr_clears (x, y, (mpfr_ptr) 0);
278 }
279
280 #define TEST_FUNCTION test_log
281 #define TEST_RANDOM_POS 8
282 #include "tgeneric.c"
283
284 int
285 main (int argc, char *argv[])
286 {
287 tests_start_mpfr ();
288
289 if (argc == 3 || argc == 4)
290 { /* tlog x prec rnd */
291 check3 (argv[1], strtoul (argv[2], NULL, 10),
292 (argc == 4) ? (mpfr_rnd_t) atoi (argv[3]) : MPFR_RNDN);
293 goto done;
294 }
295
296 special ();
297 check_worst_cases();
298
299 check2("1.01979300812244555452", MPFR_RNDN, "1.95996734891603664741e-02");
300 check2("10.0",MPFR_RNDU,"2.30258509299404590110e+00");
301 check2("6.0",MPFR_RNDU,"1.79175946922805517936");
302 check2("1.0",MPFR_RNDZ,"0.0");
303 check2("62.0",MPFR_RNDU,"4.12713438504509166905");
304 check2("0.5",MPFR_RNDZ,"-6.93147180559945286226e-01");
305 check2("3.0",MPFR_RNDZ,"1.09861228866810956006e+00");
306 check2("234375765.0",MPFR_RNDU,"1.92724362186836231104e+01");
307 check2("8.0",MPFR_RNDZ,"2.07944154167983574765e+00");
308 check2("44.0",MPFR_RNDU,"3.78418963391826146392e+00");
309 check2("1.01979300812244555452", MPFR_RNDN, "1.95996734891603664741e-02");
310
311 /* bugs found by Vincent Lefe`vre */
312 check2("0.99999599881598921769", MPFR_RNDN, "-0.0000040011920155404072924737977900999652547398000024259090423583984375");
313 check2("9.99995576063808955247e-01",MPFR_RNDZ,"-4.42394597667932383816e-06");
314 check2("9.99993687357856209097e-01",MPFR_RNDN,"-6.31266206860017342601e-06");
315 check2("9.99995223520736886691e-01",MPFR_RNDN,"-4.77649067052670982220e-06");
316 check2("9.99993025794720935551e-01",MPFR_RNDN,"-6.97422959894716163837e-06");
317 check2("9.99987549017837484833e-01",MPFR_RNDN,"-1.24510596766369924330e-05");
318 check2("9.99985901426543311032e-01",MPFR_RNDN,"-1.40986728425098585229e-05");
319 check2("9.99986053947420794330e-01",MPFR_RNDN, "-0.000013946149826301084938555592540598837558718514628708362579345703125");
320 check2("9.99971938247442126979e-01",MPFR_RNDN,"-2.80621462962173414790e-05");
321
322 /* other bugs found by Vincent Lefe`vre */
323 check2("1.18615436389927785905e+77",MPFR_RNDN,"1.77469768607706015473e+02");
324 check2("9.48868723578399476187e+77",MPFR_RNDZ,"1.79549152432275803903e+02");
325 check2("2.31822210096938820854e+89",MPFR_RNDN,"2.05770873832573869322e+02");
326
327 /* further bugs found by Vincent Lefe`vre */
328 check2("9.99999989485669482647e-01",MPFR_RNDZ,"-1.05143305726283042331e-08");
329 check2("9.99999989237970177136e-01",MPFR_RNDZ,"-1.07620298807745377934e-08");
330 check2("9.99999989239339082125e-01",MPFR_RNDN,"-1.07606609757704445430e-08");
331
332 check2("7.3890560989306504",MPFR_RNDU,"2.0000000000000004"); /* exp(2.0) */
333 check2("7.3890560989306495",MPFR_RNDU,"2.0"); /* exp(2.0) */
334 check2("7.53428236571286402512e+34",MPFR_RNDZ,"8.03073567492226345621e+01");
335 check2("6.18784121531737948160e+19",MPFR_RNDZ,"4.55717030391710693493e+01");
336 check2("1.02560267603047283735e+00",MPFR_RNDD,"2.52804164149448735987e-02");
337 check2("7.53428236571286402512e+34",MPFR_RNDZ,"8.03073567492226345621e+01");
338 check2("1.42470900831881198052e+49",MPFR_RNDZ,"113.180637144887668910087086260318756103515625");
339
340 check2("1.08013816255293777466e+11",MPFR_RNDN,"2.54055249841782604392e+01");
341 check2("6.72783635300509015581e-37",MPFR_RNDU,"-8.32893948416799503320e+01");
342 check2("2.25904918906057891180e-52",MPFR_RNDU,"-1.18919480823735682406e+02");
343 check2("1.48901209246462951085e+00",MPFR_RNDD,"3.98112874867437460668e-01");
344 check2("1.70322470467612341327e-01",MPFR_RNDN,"-1.77006175364294615626");
345 check2("1.94572026316065240791e+01",MPFR_RNDD,"2.96821731676437838842");
346 check2("4.01419512207026418764e+04",MPFR_RNDD,"1.06001772315501128218e+01");
347 check2("9.47077365236487591672e-04",MPFR_RNDZ,"-6.96212977303956748187e+00");
348 check2("3.95906157687589643802e-109",MPFR_RNDD,"-2.49605768114704119399e+02");
349 check2("2.73874914516503004113e-02",MPFR_RNDD,"-3.59766888618655977794e+00");
350 check2("9.18989072589566467669e-17",MPFR_RNDZ,"-3.69258425351464083519e+01");
351 check2("7706036453608191045959753324430048151991964994788917248.0",MPFR_RNDZ,"126.3815989984199177342816255986690521240234375");
352 check2("1.74827399630587801934e-23",MPFR_RNDZ,"-5.24008281254547156891e+01");
353 check2("4.35302958401482307665e+22",MPFR_RNDD,"5.21277441046519527390e+01");
354 check2("9.70791868689332915209e+00",MPFR_RNDD,"2.27294191194272210410e+00");
355 check2("2.22183639799464011100e-01",MPFR_RNDN,"-1.50425103275253957413e+00");
356 check2("2.27313466156682375540e+00",MPFR_RNDD,"8.21159787095675608448e-01");
357 check2("6.58057413965851156767e-01",MPFR_RNDZ,"-4.18463096196088235600e-01");
358 check2 ("7.34302197248998461006e+43",MPFR_RNDZ,"101.0049094695131799426235374994575977325439453125");
359 check2("6.09969788341579732815e+00",MPFR_RNDD,"1.80823924264386204363e+00");
360
361 x_near_one ();
362
363 test_generic (MPFR_PREC_MIN, 100, 40);
364
365 data_check ("data/log", mpfr_log, "mpfr_log");
366 bad_cases (mpfr_log, mpfr_exp, "mpfr_log", 256, -30, 30, 4, 128, 800, 50);
367
368 done:
369 tests_end_mpfr ();
370 return 0;
371 }