acos(3) - NetBSD Manual Pages

ACOS(3)                   NetBSD Programmer's Manual                   ACOS(3)


NAME

     acos, acosf - arc cosine function


LIBRARY

     Math Library (libm, -lm)


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].


RETURN VALUES

     If |x|>1, acos(x) and acosf(x) set the global variable errno to EDOM.


SEE ALSO

     asin(3), atan(3), atan2(3), cos(3), cosh(3), math(3), sin(3), sinh(3),
     tan(3), tanh(3)


STANDARDS

     The acos() function conforms to ANSI X3.159-1989 (``ANSI C'').

NetBSD 1.6                        May 2, 1991                                1