# openfermion.linalg.Davidson

Davidson algorithm to get the n states with smallest eigenvalues.

## Methods

### `get_lowest_n`

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Returns `n` smallest eigenvalues and corresponding eigenvectors for linear_operator.

Args
`n` `int`

The number of states corresponding to the smallest eigenvalues and associated eigenvectors for the linear_operator.

`initial_guess` `numpy.ndarray[complex]`

Initial guess of eigenvectors associated with the `n` smallest eigenvalues.

`max_iterations` `int`

Max number of iterations when not converging.

Returns
`success` `bool`

Indicates whether it converged, i.e. max elementwise error is smaller than eps.

`eigen_values` `numpy.ndarray[complex]`

The smallest n eigenvalues.

`eigen_vectors` `numpy.ndarray[complex]`

The smallest n eigenvectors corresponding with those eigen values.

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{ "lastModified": "Last updated 2024-04-26 UTC.", "confidential": False }