clogf3
Complex natural logarithm functions
Part of clog(3).
Usage
double complex
float complex
long double
complex
Library
Math Library (libm, -lm)
Overview
The clog(), clogf(), and clogl() functions compute the complex natural logarithm of z. with a branch cut along the negative real axis .
Return values
The clog() function returns the complex natural logarithm value, in the range of a strip mathematically unbounded along the real axis and in the interval [-I* , +I* ] along the imaginary axis. The function satisfies the relationship: clog(conj(z, Fc) = conj(clog(z, Fc).
| Argument | Return value | Comment |
| -0 + I*0 | - + I* | Divide-by-zero exception |
| raised | ||
| +0 + I*0 | - + I*0 | Divide by zero exception |
| raised | ||
| x + I* | + + I*/2 | For finite x |
| x + I* | + I* | Optionally raises invalid |
| floating-point exception | ||
| for finite x | ||
| - + I*y | + + I* | For finite positive-signed y |
| + + I*y | + + I*0 | For finite positive-signed y |
| - + I* | + + I*3/4 | |
| + + I* | + + I*/4 | |
| + I* | + + I* | |
| + I*y | + I* | Optionally raises invalid |
| floating-point exception | ||
| for finite y | ||
| + I* | + + I* | |
| + I* | + I* |
History
- FreeBSD 16.0-CURRENT (2026-10-27) to FreeBSD 13.3-RELEASE: the text shown here
- FreeBSD 13.2-RELEASE
- FreeBSD 13.1-RELEASE to FreeBSD 13.0-RELEASE
- FreeBSD 12.4-RELEASE
- FreeBSD 12.3-RELEASE
- FreeBSD 12.2-RELEASE
- FreeBSD 12.1-RELEASE
- FreeBSD 12.0-RELEASE
- FreeBSD 11.4-RELEASE
- FreeBSD 11.3-RELEASE