/*

* (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.

* See the copyright notice in the ACK home directory, in the file "Copyright".

*

* Author: Ceriel J.H. Jacobs

*/

#include <math.h>

struct complex {

double r,i;

};

_PROTOTYPE(double hypot, (double x, double y ));

_PROTOTYPE(double cabs, (struct complex p_compl ));

/* $Header$ */

double

hypot(x, y)

double x, y;

{

/* Computes sqrt(x*x+y*y), avoiding overflow */

if (x < 0) x = -x;

if (y < 0) y = -y;

if (x > y) {

double t = y;

y = x;

x = t;

}

/* sqrt(x*x+y*y) = sqrt(y*y*(x*x/(y*y)+1.0)) = y*sqrt(x*x/(y*y)+1.0) */

if (y == 0.0) return 0.0;

x /= y;

return y*sqrt(x*x+1.0);

}

double

cabs(p_compl)

struct complex p_compl;

{

return hypot(p_compl.r, p_compl.i);

}