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csqrt(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ATTRIBUTES | STANDARDS | HISTORY | SEE ALSO | COLOPHON 

csqrt(3)                 Library Functions Manual                csqrt(3)

NAME         top

       csqrt, csqrtf, csqrtl - complex square root

LIBRARY         top

       Math library (libm, -lm)

SYNOPSIS         top

       #include <complex.h>

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

DESCRIPTION         top

       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.)

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
       โ”‚ Interface                            โ”‚ Attribute     โ”‚ Value   โ”‚
       โ”œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ค
       โ”‚ csqrt(), csqrtf(), csqrtl()          โ”‚ Thread safety โ”‚ MT-Safe โ”‚
       โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜

STANDARDS         top

       C11, POSIX.1-2008.

HISTORY         top

       glibc 2.1.  C99, POSIX.1-2001.

SEE ALSO         top

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

COLOPHON         top

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Linux man-pages 6.18            2026-02-08                       csqrt(3)

Pages that refer to this page: conj(3),  sqrt(3),  complex(7)

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