NAME

       casin, casinf, casinl - complex arc sine

LIBRARY

       Math library (libm, -lm)

SYNOPSIS

       #include <complex.h>

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

DESCRIPTION

       These  functions  calculate 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))

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌───────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │Interface                                                      │ Attribute     │ Value   │
       ├───────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │casin(), casinf(), casinl()                                    │ Thread safety │ MT-Safe │
       └───────────────────────────────────────────────────────────────┴───────────────┴─────────┘

STANDARDS

       C11, POSIX.1-2008.

HISTORY

       glibc 2.1.  C99, POSIX.1-2001.

SEE ALSO

       clog(3), csin(3), complex(7)