creal(3) - BetterMan

creal(3)

get real part of a complex number

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Synopsis

#include <complex.h>
double creal(double complex 
z
);
float crealf(float complex 
z
);
long double creall(long double complex 
z
);

—

NAME

creal, crealf, creall - get real part of a complex number

Math library (libm, -lm)

bash

#include <complex.h>

bash

double creal(double complex \nz\n);\n
\nfloat crealf(float complex \nz\n);\n
\nlong double creall(long double complex \nz\n);

These functions return the real part of the complex number z.

One has:

bash


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

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
creal (), crealf (), creall ()	Thread safety	MT-Safe

GCC supports also __real__. That is a GNU extension.

C11, POSIX.1-2008.

glibc 2.1. C99, POSIX.1-2001.