diff options
author | Christopher Faylor <me@cgf.cx> | 2000-02-17 19:39:52 +0000 |
---|---|---|
committer | Christopher Faylor <me@cgf.cx> | 2000-02-17 19:39:52 +0000 |
commit | 8a0efa53e44919bcf5ccb1d3353618a82afdf8bc (patch) | |
tree | 68c3dbf3f2c6fd5d49777def9914d77b5cd4589d /newlib/libm/math/w_acos.c | |
parent | 1fd5e000ace55b323124c7e556a7a864b972a5c4 (diff) | |
download | newlib-8a0efa53e44919bcf5ccb1d3353618a82afdf8bc.zip newlib-8a0efa53e44919bcf5ccb1d3353618a82afdf8bc.tar.gz newlib-8a0efa53e44919bcf5ccb1d3353618a82afdf8bc.tar.bz2 |
import newlib-2000-02-17 snapshot
Diffstat (limited to 'newlib/libm/math/w_acos.c')
-rw-r--r-- | newlib/libm/math/w_acos.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/newlib/libm/math/w_acos.c b/newlib/libm/math/w_acos.c new file mode 100644 index 0000000..c9ca99c --- /dev/null +++ b/newlib/libm/math/w_acos.c @@ -0,0 +1,118 @@ + +/* @(#)w_acos.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 + <<acos>>, <<acosf>>---arc cosine + +INDEX + acos +INDEX + acosf + +ANSI_SYNOPSIS + #include <math.h> + double acos(double <[x]>); + float acosf(float <[x]>); + +TRAD_SYNOPSIS + #include <math.h> + double acos(<[x]>) + double <[x]>; + + float acosf(<[x]>) + float <[x]>; + + + +DESCRIPTION + + <<acos>> computes the inverse cosine (arc cosine) of the input value. + Arguments to <<acos>> must be in the range @minus{}1 to 1. + + <<acosf>> is identical to <<acos>>, except that it performs + its calculations on <<floats>>. + +RETURNS + @ifinfo + <<acos>> and <<acosf>> return values in radians, in the range of 0 to pi. + @end ifinfo + @tex + <<acos>> and <<acosf>> return values in radians, in the range of <<0>> to $\pi$. + @end tex + + If <[x]> is not between @minus{}1 and 1, the returned value is NaN + (not a number) the global variable <<errno>> is set to <<EDOM>>, and a + <<DOMAIN error>> message is sent as standard error output. + + You can modify error handling for these functions using <<matherr>>. + + +QUICKREF ANSI SVID POSIX RENTRANT + acos y,y,y,m + acosf n,n,n,m + +MATHREF + acos, [-1,1], acos(arg),,, + acos, NAN, arg,DOMAIN,EDOM + +MATHREF + acosf, [-1,1], acosf(arg),,, + acosf, NAN, argf,DOMAIN,EDOM + +*/ + +/* + * wrap_acos(x) + */ + +#include "fdlibm.h" +#include <errno.h> + +#ifndef _DOUBLE_IS_32BITS + +#ifdef __STDC__ + double acos(double x) /* wrapper acos */ +#else + double acos(x) /* wrapper acos */ + double x; +#endif +{ +#ifdef _IEEE_LIBM + return __ieee754_acos(x); +#else + double z; + struct exception exc; + z = __ieee754_acos(x); + if(_LIB_VERSION == _IEEE_ || isnan(x)) return z; + if(fabs(x)>1.0) { + /* acos(|x|>1) */ + exc.type = DOMAIN; + exc.name = "acos"; + exc.err = 0; + exc.arg1 = exc.arg2 = x; + exc.retval = 0.0; + if (_LIB_VERSION == _POSIX_) + errno = EDOM; + else if (!matherr(&exc)) { + errno = EDOM; + } + if (exc.err != 0) + errno = exc.err; + return exc.retval; + } else + return z; +#endif +} + +#endif /* defined(_DOUBLE_IS_32BITS) */ |