conj, conjf, conjl - calculate the complex conjugate

#include <complex.h>
double complex conj(double complex z);
float complex conjf(float complex z);
long double complex conjl(long double complex z);

These functions return the complex conjugate value of z. That is the value obtained by changing the sign of the imaginary part.

One has:

cabs(z) = csqrt(z * conj(z))

cabs(3), csqrt(3), complex(7)