lu_factor
LU Factorisation wrapper of:
\[LU = (\sigma \mathbf{I} - \mathbf{A})\]
In the case of A
being a sparse matrix, the sparse methods in scipy are employed
- param sigma:
Expansion frequency
- type sigma:
float
- param A:
Dynamics matrix
- type A:
csc_matrix or np.ndarray
- returns:
tuple (dense) or SuperLU (sparse) objects containing the LU factorisation
- rtype:
tuple or SuperLU