====== cabs ======
<code c>
double cabs(double complex z);
</code>

==== description of cabs ====
cabs() compute the complex absolute value ... also called modules, norm, or magnitude of z.

<code c>
#include <stdio.h> /* including standard library */
#include <complex.h>

void main(void)
{
   double complex z=4.2 + I*2.34;
   double result;

   result = cabs(z);
   printf("cabs(%f + I*%f) = %f\n",creal(z), cimag(z), result);
   return 0;
}

</code>

===== output of cabs c example =====
    cabs(4.200000 + I*2.340000) = 4.807869