Man Pages – Linux Manual Pages

creal, crealf, creall – get real part of a complex number
USAGE
#include <complex.h>

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

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cimag, cimagf, cimagl – get imaginary part of a complex number
USAGE
#include <complex.h>

double cimag(double complex z);
float cimagf(float complex z);
long double cimagl(long double complex z);

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cabs, cabsf, cabsl – absolute value of a complex number
USAGE
#include <complex.h>

double cabs(double complex z);
float cabsf(float complex z);
long double cabsl(long double complex z);

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complex – basics of complex mathematics
USAGE
#include <complex.h>

DESCRIPTION
Complex numbers are numbers of the form z = a+b*i, where a and b are
real numbers and i = sqrt(-1), so that i*i = -1.
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