csqrt, csqrtf, csqrtl — complex square root


#include <complex.h>

double complex csqrt(double complex z);
float complex csqrtf(float complex z);
long double complex csqrtl(long double complex z);

Link with -lm.


These functions calculate the complex square root of z, with a branch cut along the negative real axis. (That means that csqrt(-1+eps*I) will be close to I while csqrt(-1-eps*I) will be close to -I, if eps is a small positive real number.)


These functions first appeared in glibc in version 2.1.


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

Interface Attribute Value
csqrt(), csqrtf(), csqrtl() Thread safety MT-Safe

Conforming to

C99, POSIX.1-2001, POSIX.1-2008.

See Also

cabs(3), cexp(3), complex(7)


This page is part of release 5.04 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

Referenced By

complex(7), conj(3), sqrt(3).

The man pages csqrtf(3) and csqrtl(3) are aliases of csqrt(3).

2017-09-15 Linux Programmer's Manual