clog2, clog2f, clog2l - base-2 logarithm of a complex number
#include <complex.h>
double complex clog2(double complex z);
float complex clog2f(float complex z);
long double complex clog2l(long double complex z);The call clog2(z) is equivalent to
clog(z)/log(2).
The other functions perform the same task for float and
long double.
Note that z close to zero will cause an overflow.