#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