Mercurial > hg > octave-lyh > gnulib-hg
changeset 16656:a7869cc6ce1f
log1p tests: More tests.
* tests/test-log1p.h: New file.
* modules/log1p-tests (Files): Add tests/test-log1p.h, tests/randomd.c.
(Makefile.am): Add randomd.c to test_log1p_SOURCES.
* tests/test-log1p.c: Include <float.h> and test-log1p.h.
(main): Invoke test_function.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Sat, 10 Mar 2012 19:58:51 +0100 |
parents | e1c84de792a7 |
children | 86d5719ce2ff |
files | ChangeLog modules/log1p-tests tests/test-log1p.c tests/test-log1p.h |
diffstat | 4 files changed, 121 insertions(+), 2 deletions(-) [+] |
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--- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,12 @@ 2012-03-10 Bruno Haible <bruno@clisp.org> + log1p tests: More tests. + * tests/test-log1p.h: New file. + * modules/log1p-tests (Files): Add tests/test-log1p.h, tests/randomd.c. + (Makefile.am): Add randomd.c to test_log1p_SOURCES. + * tests/test-log1p.c: Include <float.h> and test-log1p.h. + (main): Invoke test_function. + log1p: Provide replacement for Minix and MSVC. * lib/math.in.h (log1p): New declaration. * lib/log1p.c: New file.
--- a/modules/log1p-tests +++ b/modules/log1p-tests @@ -1,7 +1,9 @@ Files: tests/test-log1p.c +tests/test-log1p.h tests/signature.h tests/macros.h +tests/randomd.c Depends-on: @@ -10,4 +12,5 @@ Makefile.am: TESTS += test-log1p check_PROGRAMS += test-log1p +test_log1p_SOURCES = test-log1p.c randomd.c test_log1p_LDADD = $(LDADD) @LOG1P_LIBM@
--- a/tests/test-log1p.c +++ b/tests/test-log1p.c @@ -23,10 +23,17 @@ #include "signature.h" SIGNATURE_CHECK (log1p, double, (double)); +#include <float.h> + #include "macros.h" -volatile double x; -double y; +#define DOUBLE double +#define HUGEVAL HUGE_VAL +#define L_(literal) literal +#define MANT_DIG DBL_MANT_DIG +#define LOG1P log1p +#define RANDOM randomd +#include "test-log1p.h" int main () @@ -36,5 +43,7 @@ y = log1p (x); ASSERT (y >= 0.4700036292 && y <= 0.4700036293); + test_function (); + return 0; }
new file mode 100644 --- /dev/null +++ b/tests/test-log1p.h @@ -0,0 +1,100 @@ +/* Test of log1p*() function family. + Copyright (C) 2012 Free Software Foundation, Inc. + + This program 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. + + This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */ + +static void +test_function (void) +{ + int i; + int j; + const DOUBLE TWO_MANT_DIG = + /* Assume MANT_DIG <= 5 * 31. + Use the identity + n = floor(n/5) + floor((n+1)/5) + ... + floor((n+4)/5). */ + (DOUBLE) (1U << ((MANT_DIG - 1) / 5)) + * (DOUBLE) (1U << ((MANT_DIG - 1 + 1) / 5)) + * (DOUBLE) (1U << ((MANT_DIG - 1 + 2) / 5)) + * (DOUBLE) (1U << ((MANT_DIG - 1 + 3) / 5)) + * (DOUBLE) (1U << ((MANT_DIG - 1 + 4) / 5)); + + /* Pole. */ + { + DOUBLE z = LOG1P (L_(-1.0)); + ASSERT (z == - HUGEVAL); + } + + /* Randomized tests. */ + { + /* Error bound, in ulps. */ + const DOUBLE err_bound = + (sizeof (DOUBLE) > sizeof (double) ? +#if defined __i386__ && defined __FreeBSD__ + /* On FreeBSD/x86 6.4, the 'long double' type really has only 53 bits of + precision in the compiler but 64 bits of precision at runtime. See + <http://lists.gnu.org/archive/html/bug-gnulib/2008-07/msg00063.html>. + The compiler has truncated all 'long double' literals in log1pl.c to + 53 bits of precision. */ + L_(900.0) +#else + L_(26.0) +#endif + : L_(13.0)); + + for (i = 0; i < SIZEOF (RANDOM); i++) + { + DOUBLE x = L_(16.0) * RANDOM[i]; /* 0.0 <= x <= 16.0 */ + DOUBLE y = LOG1P (x); + DOUBLE z = LOG1P (- x / (L_(1.0) + x)); + DOUBLE err = y + z; + ASSERT (y >= L_(0.0)); + ASSERT (z <= L_(0.0)); + ASSERT (err > - err_bound / TWO_MANT_DIG + && err < err_bound / TWO_MANT_DIG); + } + } + + { + /* Error bound, in ulps. */ + const DOUBLE err_bound = + (sizeof (DOUBLE) > sizeof (double) ? +#if defined __i386__ && defined __FreeBSD__ + /* On FreeBSD/x86 6.4, the 'long double' type really has only 53 bits of + precision in the compiler but 64 bits of precision at runtime. See + <http://lists.gnu.org/archive/html/bug-gnulib/2008-07/msg00063.html>. + The compiler has truncated all 'long double' literals in log1pl.c to + 53 bits of precision. */ + L_(1020.0) +#else + L_(65.0) +#endif + : L_(61.0)); + + for (i = 0; i < SIZEOF (RANDOM); i++) + for (j = 0; j < SIZEOF (RANDOM); j++) + { + DOUBLE x = L_(17.0) / (L_(16.0) - L_(15.0) * RANDOM[i]) - L_(2.0); + DOUBLE y = L_(17.0) / (L_(16.0) - L_(15.0) * RANDOM[j]) - L_(2.0); + /* -15/16 <= x,y <= 15 */ + DOUBLE z = L_(1.0) / ((L_(1.0) + x) * (L_(1.0) + y)) - L_(1.0); + /* Approximately (1+x) * (1+y) * (1+z) = 1. */ + DOUBLE err = LOG1P (x) + LOG1P (y) + LOG1P (z); + ASSERT (err > - err_bound / TWO_MANT_DIG + && err < err_bound / TWO_MANT_DIG); + } + } +} + +volatile DOUBLE x; +DOUBLE y;