cabs()                   Calculate Absolute Value of Complex Number
 
 #include   <math.h>
 
 double     cabs(z);                     Absolute value
 struct     complex z;                   Contains real and imaginary parts
 
    cabs() returns the absolute value of the complex number 'z'. The
    structure 'complex' (defined in <math.h>) is:
 
     struct complex {
                           double x,y;       /*real and imaginary parts */
                           };
 
    A call to cabs() is equivalent to the statement:
 
           sqrt(z.x * z.x + z.y * z.y);
 
    Returns:    Absolute value of 'z'.  On overflow, matherr() is called
                with an OVERFLOW error;  'errno' (defined in <stdlib.h>)
                is set to ERANGE (defined in <math.h>), and the value
                HUGE is returned.
 
      Notes:    Error handling can be modified by using the matherr()
                routine.
 
 
  -------------------------------- Example ---------------------------------
 
    The following statements calculate the absolute value of a complex
    number with a real part of 5.0 and an imaginary part of 12.0.
 
         #include <math.h>      /* for cabs() and struct complex */
 
         main()
         {
             struct complex z;
             double a;
 
             z.x = 5.0;      /* set real part of 'z' */
             z.y = 12.0;     /* set imaginary part of 'z' */
             a = cabs(z);    /* x = 13.0 */
         }

Seealso:


 abs() 
 fabs() 
 labs()