ndarray-inverse 0.1.9

Pure Rust Inverse and Determinant trait for ndarray Array2
Documentation 
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    fn lu_inv(&self) -> Option<Self> {
        let d = self.raw_dim();
        assert!(d[0] == d[1]);
        if let Some((l, u, p)) = self.lu() {
            let lt = l.lt_inv()?;
            let ut = u.ut_inv()?;

            Some(ut.dot(&lt).dot(&p))
        } else {
            None
        }
    }

    fn lt_inv(&self) -> Option<Self> {
        let d = self.raw_dim();
        assert!(d[0] == d[1]);
        let n = d[0];
        let mut m: Array2<T> = Array2::zeros((n, n));

        for i in 0 .. n {
            if self[(i, i)].is_zero() {
                return None;
            }
            m[(i, i)] = self[(i, i)].recip();

            for j in 0 .. i {
                for k in j .. i {
                    m[(i, j)] = m[(i, j)] + self[(i, k)] * m[(k, j)];
                }

                m[(i, j)] = -m[(i, j)] / self[(i, i)];
            }
        }

        Some(m)
    }

    fn ut_inv(&self) -> Option<Self> {
        Some(self.lt_inv()?.t().to_owned().t().to_owned())
    }