Function rin::math::wilkinson_shift

pub fn wilkinson_shift<N>(tmm: N, tnn: N, tmn: N) -> N where
    N: ComplexField, 

Computes the wilkinson shift, i.e., the 2x2 symmetric matrix eigenvalue to its tailing component tnn.

The inputs are interpreted as the 2x2 matrix: tmm tmn tmn tnn