in src/rqpoly.rs [252:265]
fn multiply_fast(&self, other: &Self) -> Self {
let mut a: Self = self.clone();
let mut b = other.clone();
if !a.is_ntt_form {
a.forward_transform();
}
if !b.is_ntt_form {
b.forward_transform();
}
let mut c = a.coeffwise_multiply(&b);
c.inverse_transform();
c
}