NAME
acos, acosf, acosl - arc cosine function
SYNOPSIS
#include <math.h>
I double acos(double x );
I float acosf(float x );
I long double acosl(long double x );
Link with
-lm.
DESCRIPTION
The
R acos ()
function calculates the arc cosine of x; that is
the value whose cosine is x.
If x falls outside the range
-1 to 1,
R acos ()
fails and errno is set.
RETURN VALUE
The
R acos ()
function returns the arc cosine in radians and the
value is mathematically defined to be between 0 and PI (inclusive).
ERRORS
CONFORMING TO
SVr4, POSIX.1-2001, 4.3BSD, C89, C99.
The
float
and
long double
variants are C99 requirements.
SEE ALSO
ČLÁNKY DO MAILU