--- /dev/null
+/* Test of expm1() function.
+ Copyright (C) 2010-2012 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/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2010. */
+
+#include <config.h>
+
+#include <math.h>
+
+#include "signature.h"
+SIGNATURE_CHECK (expm1, double, (double));
+
+#include <float.h>
+
+#include "macros.h"
+
+#define DOUBLE double
+#define L_(literal) literal
+#define MANT_DIG DBL_MANT_DIG
+#define MIN_EXP DBL_MIN_EXP
+#define EXPM1 expm1
+#define RANDOM randomd
+#include "test-expm1.h"
+
+int
+main ()
+{
+ /* A particular value. */
+ x = 0.6;
+ y = expm1 (x);
+ ASSERT (y >= 0.822118800 && y <= 0.822118801);
+
+ test_function ();
+
+ return 0;
+}
--- /dev/null
+/* Test of expm1*() 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));
+
+ /* Arguments near zero. */
+ {
+ DOUBLE x;
+
+ for (i = -1, x = L_(0.5); i >= MIN_EXP; i--, x *= L_(0.5))
+ {
+ DOUBLE y;
+
+ y = EXPM1 (x);
+#ifdef __MINGW32__ /* mingw returns a value that is slightly too small. */
+ ASSERT (y >= x * (L_(1.0) - L_(1.0) / TWO_MANT_DIG));
+#else
+ ASSERT (y >= x);
+#endif
+ ASSERT (y < L_(1.5) * x);
+
+ y = EXPM1 (- x);
+ ASSERT (y >= - x);
+ ASSERT (y < - L_(0.5) * x);
+ }
+ }
+
+ /* Randomized tests. */
+ {
+ /* Error bound, in ulps. */
+ const DOUBLE err_bound =
+ (sizeof (DOUBLE) == sizeof (long 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 expl.c to
+ 53 bits of precision. */
+ L_(1024.0)
+#else
+ L_(5.0)
+#endif
+ : L_(5.0));
+
+ for (i = 0; i < SIZEOF (RANDOM); i++)
+ {
+ DOUBLE x = L_(2.0) * RANDOM[i]; /* 0.0 <= x <= 2.0 */
+ DOUBLE y = EXPM1 (x);
+ DOUBLE z = EXPM1 (- x);
+ DOUBLE err = y + (1 + 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 (long double) ?
+#if defined __i386__ && defined __FreeBSD__
+ L_(1536.0)
+#else
+ L_(11.0)
+#endif
+ : L_(9.0));
+
+ for (i = 0; i < SIZEOF (RANDOM) / 5; i++)
+ for (j = 0; j < SIZEOF (RANDOM) / 5; j++)
+ {
+ DOUBLE x = L_(2.0) * RANDOM[i] - L_(1.0); /* -1.0 <= x <= 1.0 */
+ DOUBLE y = L_(2.0) * RANDOM[j] - L_(1.0); /* -1.0 <= y <= 1.0 */
+ DOUBLE z = - x - y;
+ /* Approximately x + y + z = 0. */
+ {
+ DOUBLE a = EXPM1 (x);
+ DOUBLE b = EXPM1 (y);
+ DOUBLE c = EXPM1 (z);
+ DOUBLE err = a + (1 + a) * (b + (1 + b) * c);
+ ASSERT (err > - err_bound / TWO_MANT_DIG
+ && err < err_bound / TWO_MANT_DIG);
+ }
+ }
+ }
+}
+
+volatile DOUBLE x;
+DOUBLE y;