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Power 6/32 Unix version 1.21

/*
 *	"@(#)c_sqrtf.c	1.1"
 */

#include "complex"

/* THIS IS BASED ON TAHOE FLOATING POINT REPR. */
#include <FP.h>

c_sqrt(r, z)
register complex *r, *z;
{
float mag, cabs();
fortran float sqrt();

if( (mag = cabs(z->real, z->imag)) == 0.)
	r->real = r->imag = 0.;
else if(z->real > 0)
	{
	r->real = sqrt(0.5 * (mag + z->real) );
	r->imag = z->imag / r->real / 2;
	}
else
	{
	r->imag = sqrt(0.5 * (mag - z->real) );
	if(z->imag < 0)
		*(unsigned long*)&(r->imag) ^= SIGN_BIT;
	r->real = z->imag / r->imag /2;
	}
}

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