Calculate several eigenvalues and corresponding eigenvectors of a matrix using ARPACK from SciPy. The eigenvalues are sorted in ascending order.
Make several iterations of the conjugate gradients and estimate so the eigenvalues of a (sparse SPD) matrix (Lanczos algorithm).
Parameters: | mtx : spmatrix or array
precond : spmatrix or array, optional
i_max : int
eps_r : float
shift : float, optional
select_indices : (min, max), optional
verbose : bool
report_step : int
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Returns: | vec : array
n_it : int
norm_rs : array
eigs : array
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