iOS Manual Pages

This document is a Mac OS X manual page. Manual pages are a command-line technology for providing documentation. You can view these manual pages locally using the man(1) command. These manual pages come from many different sources, and thus, have a variety of writing styles.

For more information about the manual page format, see the manual page for manpages(5).

CSQRT(3)                 BSD Library Functions Manual                 CSQRT(3)

NAME
     csqrt -- complex square root function

SYNOPSIS
     #include <complex.h>

     double complex
     csqrt(double complex z);

     long double complex
     csqrtl(long double complex z);

     float complex
     csqrtf(float complex z);

DESCRIPTION
     csqrt(z) computes the square root of the complex floating-point number z,
     with a branch cut on the negative real axis.  The result is in the right
     half-plane, including the imaginary axis.  For all complex z,
     csqrt(conj(z)) = conj(csqrt(z)).

SPECIAL VALUES
     The conjugate symmetry of csqrt() is used to abbreviate the specification
     of special values.

     csqrt(+-0 + 0i) returns +0 + 0i.

     csqrt(x + inf i) returns inf + inf i for all x (including NaN).

     csqrt(x + NaN i) returns NaN + NaN i.

     csqrt(-inf + yi) returns 0 + inf i for any positively-signed finite y.

     csqrt(inf + yi) returns inf + 0i for any positively-signed finite y.

     csqrt(-inf + NaN i) returns NaN + inf i.

     csqrt(inf + NaN i) returns inf + NaN i.

     csqrt(NaN + yi) returns NaN + NaN i.

     csqrt(NaN + NaN i) returns NaN + NaN i.

NOTES
     If z is in the upper half-plane, then csqrt(z) is in the upper-right
     quadrant of the complex plane.  If z is in the lower half-plane, then
     csqrt(z) is in the lower-right quadrant of the complex plane.

SEE ALSO
     complex(3)

STANDARDS
     The csqrt() function conforms to ISO/IEC 9899:1999(E).

4th Berkeley Distribution      October 10, 2006      4th Berkeley Distribution