qrunch.quantum.estimators.memory_restricted_estimator

Module containing the a memory restricted estimator.

Classes

Class for estimating observables using the memory restricted estimator.

class MemoryRestrictedEstimator

Bases: Estimator

Class for estimating observables using the memory restricted estimator.

__init__(options: MemoryRestrictedSimulatorOptions | None = None, error_mitigator: EstimatorErrorMitigator | None = None) → None

Initiate an instance of the MemoryRestrictedEstimator.

Parameters:

options (MemoryRestrictedSimulatorOptions | None) – Options to be used in the MemoryRestrictedEstimator.
error_mitigator (EstimatorErrorMitigator | None) – Error mitigator to be used for encoding the observable or circuit more error resistantly.

Return type:

None

clear_cache() → None

Clear the measurement cache.

has_spin_particle_conservation() → bool

Return True, if the estimator is set to use spin particle conservation.

has_total_particle_conservation() → bool

Return True, if the estimator is set to use total particle conservation.

Estimate the value of the observables using the circuit state.

For each observable the following will be calculated: <circuit|observable|circuit>.

Parameters:

observables (Sequence[int | float | complex | Expression[PauliOperators]] | int | float | complex | Expression[PauliOperators] | Sequence[HermitianPauliSum] | HermitianPauliSum) – Observable(s) to be estimated.
circuits (Circuit | Sequence[Circuit]) – States to make estimation from.
shots (int | None) – number of shots or None if using a full state vector calculation.

Return type:

supports_shots_equals_none() → bool

Return whether the estimator supports shots = None.

The memory restricted estimator does currently only support shots=None