pele.utils.hessian.get_eig#
- pele.utils.hessian.get_eig(hess, **kwargs)[source]#
return the eigenvalue and eigenvectors of a Hessian (symmetric)
The following is from numpy.linalg.eigh
Return the eigenvalues and eigenvectors of a Hermitian or symmetric matrix.
Returns two objects, a 1-D array containing the eigenvalues of a, and a 2-D square array or matrix (depending on the input type) of the corresponding eigenvectors (in columns).
- Parameters:
- aarray_like, shape (M, M)
A complex Hermitian or real symmetric matrix.
- UPLO{‘L’, ‘U’}, optional
Specifies whether the calculation is done with the lower triangular part of a (‘L’, default) or the upper triangular part (‘U’).
- Returns:
- wndarray, shape (M,)
The eigenvalues, not necessarily ordered.
- vndarray, or matrix object if a is, shape (M, M)
The column
v[:, i]is the normalized eigenvector corresponding to the eigenvaluew[i].
- Raises:
- LinAlgError
If the eigenvalue computation does not converge.