#include "f2c.h" extern void sig_die (char *, int); void z_div (doublecomplex * c, doublecomplex * a, doublecomplex * b) { 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; }