clog(3)

NAME

clog, clogf, clogl — complex natural logarithm

SYNOPSIS

/* -lm */
#include <complex.h>

double complex
clog(double complex z);

float complex
clogf(float complex z);

long double complex
clogl(long double complex z);

DESCRIPTION

The clog(), clogf() and clogl() functions compute the complex logarithm to the base e (2.718...) of z.

If z = x + iy, then

clog(z) = log(sqrt(x^2 + y^2)) + i atan(y / x).

RETURN VALUES

The clog(), clogf() and clogl() functions return the complex logarithm to the base e of z with imaginary part in the interval [-Pi, Pi], and unbounded real part.

SEE ALSO

cexp(3), cpow(3)

STANDARDS

The clog(), clogf() and clogl() functions conform to ISO/IEC 9899:1999 (“ISO C99”).