casin(3) Library Functions Manual casin(3)
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 attrib-
utes(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)
Linux man-pages 6.7 2023-10-31 casin(3)
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