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#include "f2c.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef KR_headers
extern VOID sig_die();
VOID z_div(c, a, b) doublecomplex *a, *b, *c;
#else
extern void sig_die(const 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) {
#ifdef IEEE_COMPLEX_DIVIDE
if (a->i != 0 || a->r != 0)
abi = 1.;
c->i = c->r = abi / abr;
return;
#else
sig_die("complex division by zero", 1);
#endif
}
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;
}
#ifdef __cplusplus
}
#endif
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