Function linxal::properties::is_diagonal_tol

pub fn is_diagonal_tol<T, D, F>(mat: &ArrayBase<D, Ix2>, tolerance: F) -> bool where
    T: LinxalImplScalar,
    D: Data<Elem = T>,
    F: Into<T::RealPart>, 

Returns true iff the matrix is diagonal, within a given tolerance.

The input matrix need not be square to be diagonal.