scipy.linalg.cho_solve_banded#
- scipy.linalg.cho_solve_banded(cb_and_lower, b, overwrite_b=False, check_finite=True)[source]#
Solve the linear equations
A x = b
, given the Cholesky factorization of the banded HermitianA
.- Parameters
- (cb, lower)tuple, (ndarray, bool)
cb is the Cholesky factorization of A, as given by cholesky_banded. lower must be the same value that was given to cholesky_banded.
- barray_like
Right-hand side
- overwrite_bbool, optional
If True, the function will overwrite the values in b.
- check_finitebool, optional
Whether to check that the input matrices contain only finite numbers. Disabling may give a performance gain, but may result in problems (crashes, non-termination) if the inputs do contain infinities or NaNs.
- Returns
- xarray
The solution to the system A x = b
See also
cholesky_banded
Cholesky factorization of a banded matrix
Notes
New in version 0.8.0.
Examples
>>> from scipy.linalg import cholesky_banded, cho_solve_banded >>> Ab = np.array([[0, 0, 1j, 2, 3j], [0, -1, -2, 3, 4], [9, 8, 7, 6, 9]]) >>> A = np.diag(Ab[0,2:], k=2) + np.diag(Ab[1,1:], k=1) >>> A = A + A.conj().T + np.diag(Ab[2, :]) >>> c = cholesky_banded(Ab) >>> x = cho_solve_banded((c, False), np.ones(5)) >>> np.allclose(A @ x - np.ones(5), np.zeros(5)) True