gnulib/tests/test-atan2.c

/* Test of atan2() function.
   Copyright (C) 2010-2020 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 <https://www.gnu.org/licenses/>.  */

/* Written by Bruno Haible <bruno@clisp.org>, 2010.  */

#include <config.h>

#include <math.h>

#include "signature.h"
SIGNATURE_CHECK (atan2, double, (double, double));

#include "macros.h"

volatile double x;
volatile double y;
double z;

int
main ()
{
  /* A particular value in the first quadrant.  */
  x = 0.6;
  y = 0.8;
  z = atan2 (y, x);
  ASSERT (z >= 0.9272952180 && z <= 0.9272952181);

  /* A particular value in the second quadrant.  */
  x = -0.6;
  y = 0.8;
  z = atan2 (y, x);
  ASSERT (z >= 2.214297435 && z <= 2.214297436);

  /* A particular value in the third quadrant.  */
  x = -0.6;
  y = -0.8;
  z = atan2 (y, x);
  ASSERT (z >= -2.214297436 && z <= -2.214297435);

  /* A particular value in the fourth quadrant.  */
  x = 0.6;
  y = -0.8;
  z = atan2 (y, x);
  ASSERT (z >= -0.9272952181 && z <= -0.9272952180);

  return 0;
}