w_atan2.c

/*
 * Copyright (c) 1998, 2001, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

/*
 * wrapper atan2(y,x)
 */

#include "fdlibm.h"


#ifdef __STDC__
        double atan2(double y, double x)        /* wrapper atan2 */
#else
        double atan2(y,x)                       /* wrapper atan2 */
        double y,x;
#endif
{
#ifdef _IEEE_LIBM
        return __ieee754_atan2(y,x);
#else
        double z;
        z = __ieee754_atan2(y,x);
        if(_LIB_VERSION == _IEEE_||isnan(x)||isnan(y)) return z;
        if(x==0.0&&y==0.0) {
                return __kernel_standard(y,x,3); /* atan2(+-0,+-0) */
        } else
            return z;
#endif
}