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+
+/* @(#)w_atan2.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ *
+ */
+
+/*
+FUNCTION
+ <<atan2>>, <<atan2f>>---arc tangent of y/x
+
+INDEX
+ atan2
+INDEX
+ atan2f
+
+ANSI_SYNOPSIS
+ #include <math.h>
+ double atan2(double <[y]>,double <[x]>);
+ float atan2f(float <[y]>,float <[x]>);
+
+TRAD_SYNOPSIS
+ #include <math.h>
+ double atan2(<[y]>,<[x]>);
+ double <[y]>;
+ double <[x]>;
+
+ float atan2f(<[y]>,<[x]>);
+ float <[y]>;
+ float <[x]>;
+
+DESCRIPTION
+
+<<atan2>> computes the inverse tangent (arc tangent) of <[y]>/<[x]>.
+<<atan2>> produces the correct result even for angles near
+@ifnottex
+pi/2 or -pi/2
+@end ifnottex
+@tex
+$\pi/2$ or $-\pi/2$
+@end tex
+(that is, when <[x]> is near 0).
+
+<<atan2f>> is identical to <<atan2>>, save that it takes and returns
+<<float>>.
+
+RETURNS
+<<atan2>> and <<atan2f>> return a value in radians, in the range of
+@ifnottex
+-pi to pi.
+@end ifnottex
+@tex
+$-\pi$ to $\pi$.
+@end tex
+
+You can modify error handling for these functions using <<matherr>>.
+
+PORTABILITY
+<<atan2>> is ANSI C. <<atan2f>> is an extension.
+
+
+*/
+
+/*
+ * wrapper atan2(y,x)
+ */
+
+#include "fdlibm.h"
+#include <errno.h>
+
+#ifndef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+ double atan2(double y, double x) /* wrapper atan2 */
+#else
+ double atan2(y,x) /* wrapper atan2 */
+ double y,x;
+#endif
+{
+ return __ieee754_atan2(y,x);
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */