acos(), acosf()

arc cosine function 

Function


SYNOPSIS

#include <math.h>

double acos(double x)

float acosf(float x)


DESCRIPTION

The acos() and acosf() functions compute the principal value of the arc cosine of x in the range [0, Pi].

An application wishing to check for error situations should set errno to 0 before calling acos(). If errno is non-zero on return, or the value NaN is returned, an error has occurred.

The acosf() function is a single-precision version of acos().


PARAMETERS

x 

Value between -1 and +1 whose arc cosine is to be calculated.


RETURN VALUES

If |x|>1, acos(x) and acosf(x) return the following values based on the current math mode:


CONFORMANCE

acos(): ANSI/ISO 9899-1990

acosf(): PTC MKS Toolkit UNIX APIs extension


MULTITHREAD SAFETY LEVEL

MT-Safe.


PORTING ISSUES

None.


AVAILABILITY

PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Professional Developers 64-Bit Edition
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition


SEE ALSO

Functions:
asin(), atan(), atan2(), cos(), cosh(), math(), matherr(), sin(), sinh(), tan(), tanh()


PTC MKS Toolkit 10.3 Documentation Build 39.