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Power 6/32 Unix version 1.21

/*
 *	@(#)z_div.c	2.1	6/7/85
 */

#include "complex"
#include <stdio.h>
#include <errno.h>

/* THIS IS BASED ON TAHOE FP REPRESENTATION! */
#include <FP.h>

z_div(c, a, b)
dcomplex *a, *b, *c;
{
double ratio, den;
double abr, abi;

if( (abr = b->dreal) < 0.)
	*((long int *)&abr) ^= SIGN_BIT;
if( (abi = b->dimag) < 0.)
	*((long int *)&abi) ^= SIGN_BIT;
if( abr <= abi )
	{
	if(abi == 0) {
		fprintf( stderr, "Double complex division by zero\n" );
		/* f77_abort(EDOM); */
	}
	ratio = b->dreal / b->dimag ;
	den = b->dimag * (1 + ratio*ratio);
	c->dreal = (a->dreal*ratio + a->dimag) / den;
	c->dimag = (a->dimag*ratio - a->dreal) / den;
	}

else
	{
	ratio = b->dimag / b->dreal ;
	den = b->dreal * (1 + ratio*ratio);
	c->dreal = (a->dreal + a->dimag*ratio) / den;
	c->dimag = (a->dimag - a->dreal*ratio) / den;
	}

}

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