freebsd-skq/lib/libF77/z_div.c
joerg 38d2602fc1 Update to the most recent version. Among other things, this also solves
the function naming problem for complex double function i've recently
aksed for in -committers.  (The recently committed rev 1.5 of proc.c
was actually also part of this update.)

Should the mailing lists come to an agreement that f2c better belongs
into the ports, this could be done nevertheless.  For the time being,
we've at least got a current version now.

Thanks, Steve!

Submitted by:	Steve Kargl <sgk@troutmask.apl.washington.edu>
1999-02-03 17:23:49 +00:00

37 lines
709 B
C

#include "f2c.h"
#ifdef KR_headers
extern VOID sig_die();
VOID z_div(c, a, b) doublecomplex *a, *b, *c;
#else
extern void sig_die(char*, int);
void z_div(doublecomplex *c, doublecomplex *a, doublecomplex *b)
#endif
{
double ratio, den;
double abr, abi, cr;
if( (abr = b->r) < 0.)
abr = - abr;
if( (abi = b->i) < 0.)
abi = - abi;
if( abr <= abi )
{
if(abi == 0)
sig_die("complex division by zero", 1);
ratio = b->r / b->i ;
den = b->i * (1 + ratio*ratio);
cr = (a->r*ratio + a->i) / den;
c->i = (a->i*ratio - a->r) / den;
}
else
{
ratio = b->i / b->r ;
den = b->r * (1 + ratio*ratio);
cr = (a->r + a->i*ratio) / den;
c->i = (a->i - a->r*ratio) / den;
}
c->r = cr;
}