mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-29 12:03:03 +00:00
30 lines
492 B
C
30 lines
492 B
C
|
#include "f2c.h"
|
||
|
|
|
||
|
|
#ifdef KR_headers
|
||
|
|
double sqrt(), f__cabs();
|
||
|
|
VOID z_sqrt(r, z) doublecomplex *r, *z;
|
||
|
|
#else
|
||
|
|
#undef abs
|
||
|
|
#include "math.h"
|
||
|
|
extern double f__cabs(double, double);
|
||
|
|
void z_sqrt(doublecomplex *r, doublecomplex *z)
|
||
|
|
#endif
|
||
|
|
{
|
||
|
|
double mag;
|
||
|
|
|
||
|
|
if( (mag = f__cabs(z->r, z->i)) == 0.)
|
||
|
|
r->r = r->i = 0.;
|
||
|
|
else if(z->r > 0)
|
||
|
|
{
|
||
|
|
r->r = sqrt(0.5 * (mag + z->r) );
|
||
|
|
r->i = z->i / r->r / 2;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
r->i = sqrt(0.5 * (mag - z->r) );
|
||
|
|
if(z->i < 0)
|
||
|
|
r->i = - r->i;
|
||
|
|
r->r = z->i / r->i / 2;
|
||
|
|
}
|
||
|
|
}
|