cpow.3   [plain text]


.\" Copyright (c) 2006 Apple Computer
.\"
.Dd December 11, 2006
.Dt CPOW 3
.Os BSD 4
.Sh NAME
.Nm cpow
.Nd complex power function
.Sh SYNOPSIS
.Fd #include <complex.h>
.Ft double complex
.Fn cpow "double complex x, double complex y"
.Ft long double complex
.Fn cpowl "long double complex x, long double complex y"
.Ft float complex
.Fn cpowf "float complex x, float complex y"
.Sh DESCRIPTION
.Fn cpow "x, y"
returns the complex number
.Fa x 
raised to the complex power
.Fa y .
.Pp
cpow(x,y) is equivalent to cexp(y * clog(x)).  As such,
.Fn cpow "x, y"
has a branch cut along the negative real axis for the first argument, and the equality
cpow(conj(x),conj(y)) = conj(cpow(x,y)) holds for all x and y.
.Sh SPECIAL VALUES
For special values, see clog and cexp.
.Sh SEE ALSO
.Xr cexp 3
.Xr clog 3
.Xr complex 3
.Sh STANDARDS
The
.Fn cpow
function conforms to ISO/IEC 9899:1999(E).