CREAL(3) Linux Programmers Manual CREAL(3)
creal, crealf, creall - get real part of a complex number
double creal(double complex z);
float crealf(float complex z);
long double creall(long double complex z);
Link with -lm.
The creal() function returns the real part of the complex number z.
z = creal(z) + I * cimag(z)
The gcc supports also __real__. That is a GNU extension.
cabs(3), cimag(3), complex(7)
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