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Diffstat (limited to 'newlib/libm/math/w_atan2.c')
-rw-r--r-- | newlib/libm/math/w_atan2.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/newlib/libm/math/w_atan2.c b/newlib/libm/math/w_atan2.c new file mode 100644 index 00000000000..f3e344ea614 --- /dev/null +++ b/newlib/libm/math/w_atan2.c @@ -0,0 +1,90 @@ + +/* @(#)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) */ |