Poly divide(Poly const &a, Poly const &b, Poly &r) {
Poly c;
r = a; // remainder
assert(!b.empty());
const unsigned k = a.degree();
const unsigned l = b.degree();
c.resize(k, 0.);
for(unsigned i = k; i >= l; i--) {
assert(i >= 0);
double ci = r.back()/b.back();
c[i-l] += ci;
Poly bb = ci*b;
//std::cout << ci <<"*(" << b.shifted(i-l) << ") = "
// << bb.shifted(i-l) << " r= " << r << std::endl;
r -= bb.shifted(i-l);
r.pop_back();
}
//std::cout << "r= " << r << std::endl;
r.normalize();
c.normalize();
return c;
}
