devectorize

devectorize(vectorized_mat, method='col')

Devectorize a vectorized square matrix.

Parameters

• vectorized_mat (ndarray) – a vectorized density matrix.

• method (str) –

  the method of devectorization. Allowed values are

  • ’col’ (default): flattens to column-major vector.

  • ’row’: flattens to row-major vector.

  • ’pauli’: flattens in the n-qubit Pauli basis.

  • ’pauli-weights’: flattens in the n-qubit Pauli basis ordered by weight.

Returns

the resulting matrix.

Return type

ndarray

Raises

Exception – if input state is not a n-qubit state