Function mqpoly_div_ntt 

pub fn mqpoly_div_ntt(logn: u32, a: &mut [u16], b: &[u16]) -> bool

Divide polynomial a by polynomial b; both must be in NTT representation.

If b is invertible (none of its NTT coefficients are zero), then this returns true; otherwise, this returns false and the impacted result coefficients are set to the internal representation of zero.