cirq.final_state_vector

Returns the state vector resulting from acting operations on a state.

cirq.final_state_vector(
    program: 'cirq.CIRCUIT_LIKE',
    *,
    initial_state: 'cirq.STATE_VECTOR_LIKE' = 0,
    param_resolver: 'cirq.ParamResolverOrSimilarType' = None,
    qubit_order: 'cirq.QubitOrderOrList' = cirq.QubitOrder.DEFAULT,
    ignore_terminal_measurements: bool = False,
    dtype: Type[np.complexfloating] = np.complex64,
    seed: 'cirq.RANDOM_STATE_OR_SEED_LIKE' = None
) -> np.ndarray

Used in the notebooks

Used in the guide

By default the input state is the computational basis zero state, in which case the output is just the first column of the implied unitary matrix.

program The circuit, gate, operation, or tree of operations to apply to the initial state in order to produce the result.
initial_state If an int, the state is set to the computational basis state corresponding to this state. Otherwise if this is a np.ndarray it is the full initial state. In this case it must be the correct size, be normalized (an L2 norm of 1), and be safely castable to an appropriate dtype for the simulator.
param_resolver Parameters to run with the program.
qubit_order Determines the canonical ordering of the qubits. This is often used in specifying the initial state, i.e. the ordering of the computational basis states.
ignore_terminal_measurements When set, measurements at the end of the circuit are ignored instead of causing the method to fail.
dtype The numpy.dtype used by the simulation. Typically one of numpy.complex64 or numpy.complex128.
seed The random seed to use for this simulator.

The state vector resulting from applying the given unitary operations to the desired initial state. Specifically, a numpy array containing the amplitudes in np.kron order, where the order of arguments to kron is determined by the qubit order argument (which defaults to just sorting the qubits that are present into an ascending order).

ValueError If the program doesn't have a well defined final state because it has non-unitary gates.