acosh(3) - NetBSD Manual Pages

ACOSH(3)                NetBSD Library Functions Manual               ACOSH(3)


NAME

     acosh, acoshf, acoshl -- inverse hyperbolic cosine function


LIBRARY

     Math Library (libm, -lm)


SYNOPSIS

     #include <math.h>

     double
     acosh(double x);

     float
     acoshf(float x);

     long double
     acoshl(long double x);


DESCRIPTION

     The acosh(), acoshf(), and acoshl() functions compute the inverse hyper-
     bolic cosine of the real argument x.


RETURN VALUES

     If x is less than one, acosh(x), acoshf(x), and acoshl(x) return NaN and
     set the global variable errno to EDOM.


SEE ALSO

     asinh(3), atanh(3), exp(3), math(3)


STANDARDS

     The acosh() function conforms to ISO/IEC 9899:1999 (``ISO C99'').


HISTORY

     The acosh() function appeared in 4.3BSD.

NetBSD 10.99                   January 29, 2013                   NetBSD 10.99