cirq.validate_density_matrix

Checks that the given density matrix is valid.

cirq.validate_density_matrix(
    density_matrix: np.ndarray,
    *,
    qid_shape: tuple[int, ...],
    dtype: (DTypeLike | None) = None,
    atol: float = 1e-07
) -> None

density_matrix The density matrix to validate.
qid_shape The expected qid shape.
dtype The expected dtype.
atol Absolute numerical tolerance.

ValueError The density matrix does not have the correct dtype.
ValueError The density matrix does not have the correct shape. It should be a square matrix with dimension prod(qid_shape).
ValueError The density matrix is not Hermitian.
ValueError The density matrix does not have trace 1.
ValueError The density matrix is not positive semidefinite.