CASIN(3) Linux Programmer s Manual CASIN(3)

NAME casin, casinf, casinl - complex arc sine

SYNOPSIS #include <complex.h>

double complex casin(double complex z); float complex casinf(float complex z); long double complex casinl(long double complex z);

Link with -lm.

DESCRIPTION The casin() function calculates the complex arc sine of z. If y = casin(z), then z = csin(y). The real part of y is chosen in the interval [-pi/2,pi/2].

One has:

casin(z) = -i clog(iz + csqrt(1 - z * z))

VERSIONS These functions first appeared in glibc in version 2.1.


SEE ALSO ccos(3), clog(3), complex(7)

COLOPHON This page is part of release 3.22 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at

2008-08-11 CASIN(3)