/* Test of modf*() function family. Copyright (C) 2012-2015 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 . */ static void test_function (void) { int i; 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)); /* Randomized tests. */ for (i = 0; i < SIZEOF (RANDOM); i++) { DOUBLE x = RANDOM[i]; /* 0.0 <= x < 1.0 */ DOUBLE y; DOUBLE z; y = MODF (x, &z); ASSERT (z == L_(0.0)); ASSERT (y == x); y = MODF (- x, &z); ASSERT (z == L_(0.0)); ASSERT (y == - x); y = MODF (L_(1.0) + x, &z); ASSERT (z == L_(1.0)); y -= x; ASSERT (y >= - L_(1.0) / TWO_MANT_DIG); ASSERT (y <= L_(1.0) / TWO_MANT_DIG); y = MODF (- L_(1.0) - x, &z); ASSERT (z == - L_(1.0)); y -= - x; ASSERT (y >= - L_(1.0) / TWO_MANT_DIG); ASSERT (y <= L_(1.0) / TWO_MANT_DIG); } } volatile DOUBLE x; DOUBLE y; DOUBLE z;