creal man page


This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

creal, crealf, creall — complex real functions


#include <complex.h>

double creal(double complex z);
float crealf(float complex z);
long double creall(long double complex z);


The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1‐2008 defers to the ISO C standard.

These functions shall compute the real part of z.

Return Value

These functions shall return the real part value.


No errors are defined.

The following sections are informative.

Application Usage

For a variable z of type complex:

z == creal(z) + cimag(z)*I

See Also

carg(), cimag(), conj(), cproj()

The Base Definitions volume of POSIX.1‐2008, <complex.h>


2013 IEEE/The Open Group POSIX Programmer's Manual