2.9BSD - /usr/src/lib/libF77/z_div.c

   1: /*
   2:  *	"@(#)z_div.c	1.1"
   3:  */
   4: 
   5: #include "complex"
   6: 
   7: z_div(c, a, b)
   8: dcomplex *a, *b, *c;
   9: {
  10: double ratio, den;
  11: double abr, abi;
  12: 
  13: if( (abr = b->dreal) < 0.)
  14:     abr = - abr;
  15: if( (abi = b->dimag) < 0.)
  16:     abi = - abi;
  17: if( abr <= abi )
  18:     {
  19:     if(abi == 0)
  20:         abort(); /* fatal("complex division by zero"); */
  21:     ratio = b->dreal / b->dimag ;
  22:     den = b->dimag * (1 + ratio*ratio);
  23:     c->dreal = (a->dreal*ratio + a->dimag) / den;
  24:     c->dimag = (a->dimag*ratio - a->dreal) / den;
  25:     }
  26: 
  27: else
  28:     {
  29:     ratio = b->dimag / b->dreal ;
  30:     den = b->dreal * (1 + ratio*ratio);
  31:     c->dreal = (a->dreal + a->dimag*ratio) / den;
  32:     c->dimag = (a->dimag - a->dreal*ratio) / den;
  33:     }
  34: 
  35: }

Defined functions