ACOS 3CW "09 March 2006" "mathcw-1.00"

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUES
ERRORS
SEE ALSO

NAME

acosf, acos, acosl, acosw, acosq, acosll, acosdf, acosd, acosdl, acosdll - arc cosine function

SYNOPSIS

cc [ flags ] -I/usr/local/include file(s) -L/usr/local/lib -lmcw [ ... ]

#include <mathcw.h>

extern float acosf (float x);

extern double acos (double x);

extern long double acosl (long double x);

extern __float80 acosw (__float80 x);

extern __float128 acosq (__float128 x);

extern long_long_double acosll (long_long_double x);

extern decimal_float acosdf (decimal_float x);

extern decimal_double acosd (decimal_double x);

extern decimal_long_double acosdl (decimal_long_double x);

extern decimal_long_long_double acosdll (decimal_long_long_double x);

NB: Functions with prototypes containing underscores in type names may be available only with certain extended compilers.

DESCRIPTION

Compute the principal value of the arc cosine function. The value of x should be in the range [-1,+1], for which the function range is [pi,0].

RETURN VALUES

For in-range arguments, the returned value is in the range [+0,+pi]. Otherwise, the returned value is a quiet NaN.

ERRORS

For out-of-range, Infinity and NaN arguments, the returned value is a quiet NaN, and errno is set to EDOM.