qiskit.circuit.QuantumCircuit.snapshot_expectation_value

QuantumCircuit.snapshot_expectation_value(label, op, qubits, single_shot=False, variance=False)

Take a snapshot of expectation value <O> of an Operator.

Parameters

• label (str) – a snapshot label to report the result

• op (Operator) – operator to snapshot

• qubits (list) – the qubits to snapshot.

• single_shot (bool) – return list for each shot rather than average [Default: False]

• variance (bool) – compute variance of values [Default: False]

Returns

with attached instruction.

Return type

QuantumCircuit

Raises

ExtensionError – if snapshot is invalid.

Note

This method will be deprecated after the qiskit-aer 0.8 release. It has been superseded by the qiskit.providers.aer.library.save_expectation_value() and qiskit.providers.aer.library.save_expectation_value_variance() circuit methods.