tests/lib/libm/t_acos.c

   1 /* $NetBSD: t_acos.c,v 1.10 2014/03/05 20:14:46 dsl Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2011 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Jukka Ruohonen.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include <atf-c.h>
  33 #include <math.h>
  34 #include "t_libm.h"
  35
  36 /*
  37  * acos(3) and acosf(3)
  38  */
  39
  40 ATF_LIBM_TEST(acos_is_nan, "Test acos/acosf(x) == NaN, x = NaN, +/-Inf, ![-1..1]")
  41 {
  42         static const double x[] = {
  43             -1.000000001, 1.000000001,
  44             -1.0000001, 1.0000001,
  45             -1.1, 1.1,
  46 #ifndef __vax__
  47             T_LIBM_NAN,
  48             T_LIBM_MINUS_INF, T_LIBM_PLUS_INF,
  49 #endif
  50         };
  51         unsigned int i;
  52
  53         for (i = 0; i < __arraycount(x); i++) {
  54                 T_LIBM_CHECK_NAN(i, acos, x[i]);
  55                 if (i < 2)
  56                         /* Values are too small for float */
  57                         continue;
  58                 T_LIBM_CHECK_NAN(i, acosf, x[i]);
  59         }
  60 }
  61
  62 ATF_LIBM_TEST(acos_inrange, "Test acos/acosf(x) for some valid values")
  63 {
  64         static const struct {
  65                 double x;
  66                 double y;
  67         } values[] = {
  68                 { -1,    M_PI,              },
  69                 { -0.99, 3.000053180265366, },
  70                 { -0.5,  2.094395102393195, },
  71                 { -0.1,  1.670963747956456, },
  72                 {  0,    M_PI / 2,          },
  73                 {  0.1,  1.470628905633337, },
  74                 {  0.5,  1.047197551196598, },
  75                 {  0.99, 0.141539473324427, },
  76         };
  77         unsigned int i;
  78
  79         /*
  80          * Note that acos(x) might be calculated as atan2(sqrt(1-x*x),x).
  81          * This means that acos(-1) is atan2(+0,-1), if the sign is wrong
  82          * the value will be -M_PI (atan2(-0,-1)) not M_PI.
  83          */
  84
  85         for (i = 0; i < __arraycount(values); i++) {
  86                 T_LIBM_CHECK(i, acos, values[i].x, values[i].y, 1.0e-15);
  87                 T_LIBM_CHECK(i, acosf, values[i].x, values[i].y, 1.0e-5);
  88         }
  89 }
  90
  91 ATF_LIBM_TEST(acos_is_plus_zero, "Test acosf(1.0) == +0.0")
  92 {
  93         T_LIBM_CHECK_PLUS_ZERO(0, acos, 1.0);
  94         T_LIBM_CHECK_PLUS_ZERO(0, acosf, 1.0);
  95 }
  96
  97 ATF_TP_ADD_TCS(tp)
  98 {
  99
 100         ATF_TP_ADD_TC(tp, acos_inrange);
 101         ATF_TP_ADD_TC(tp, acos_is_nan);
 102         ATF_TP_ADD_TC(tp, acos_is_plus_zero);
 103
 104         return atf_no_error();
 105 }