166 lines
11 KiB
Plaintext
166 lines
11 KiB
Plaintext
---
|
||
title: MaximumLikelihoodAmplitudeEstimation
|
||
description: API reference for qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation
|
||
in_page_toc_min_heading_level: 1
|
||
python_api_type: class
|
||
python_api_name: qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation
|
||
---
|
||
|
||
# MaximumLikelihoodAmplitudeEstimation
|
||
|
||
<Class id="qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation" isDedicatedPage={true} github="https://github.com/qiskit/qiskit/tree/stable/0.46/qiskit/algorithms/amplitude_estimators/mlae.py" signature="qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation(evaluation_schedule, minimizer=None, quantum_instance=None, sampler=None)" modifiers="class">
|
||
Bases: [`AmplitudeEstimator`](qiskit.algorithms.AmplitudeEstimator "qiskit.algorithms.amplitude_estimators.amplitude_estimator.AmplitudeEstimator")
|
||
|
||
The Maximum Likelihood Amplitude Estimation algorithm.
|
||
|
||
This class implements the quantum amplitude estimation (QAE) algorithm without phase estimation, as introduced in \[1]. In comparison to the original QAE algorithm \[2], this implementation relies solely on different powers of the Grover operator and does not require additional evaluation qubits. Finally, the estimate is determined via a maximum likelihood estimation, which is why this class in named `MaximumLikelihoodAmplitudeEstimation`.
|
||
|
||
**References**
|
||
|
||
**\[1]: Suzuki, Y., Uno, S., Raymond, R., Tanaka, T., Onodera, T., & Yamamoto, N. (2019).**
|
||
|
||
Amplitude Estimation without Phase Estimation. [arXiv:1904.10246](https://arxiv.org/abs/1904.10246).
|
||
|
||
**\[2]: Brassard, G., Hoyer, P., Mosca, M., & Tapp, A. (2000).**
|
||
|
||
Quantum Amplitude Amplification and Estimation. [arXiv:quant-ph/0005055](http://arxiv.org/abs/quant-ph/0005055).
|
||
|
||
<Admonition title="Deprecated since version 0.24.0" type="danger">
|
||
`qiskit.algorithms.amplitude_estimators.mlae.MaximumLikelihoodAmplitudeEstimation.__init__()`’s argument `quantum_instance` is deprecated as of qiskit-terra 0.24.0. It will be removed no earlier than 3 months after the release date. Instead, use the `sampler` argument. See [https://qisk.it/algo\_migration](https://qisk.it/algo_migration) for a migration guide.
|
||
</Admonition>
|
||
|
||
**Parameters**
|
||
|
||
* **evaluation\_schedule** ([*list*](https://docs.python.org/3/library/stdtypes.html#list "(in Python v3.12)")*\[*[*int*](https://docs.python.org/3/library/functions.html#int "(in Python v3.12)")*] |* [*int*](https://docs.python.org/3/library/functions.html#int "(in Python v3.12)")) – If a list, the powers applied to the Grover operator. The list element must be non-negative. If a non-negative integer, an exponential schedule is used where the highest power is 2 to the integer minus 1: \[id, Q^2^0, …, Q^2^(evaluation\_schedule-1)].
|
||
* **minimizer** (*MINIMIZER | None*) – A minimizer used to find the minimum of the likelihood function. Defaults to a brute search where the number of evaluation points is determined according to `evaluation_schedule`. The minimizer takes a function as first argument and a list of (float, float) tuples (as bounds) as second argument and returns a single float which is the found minimum.
|
||
* **quantum\_instance** ([*QuantumInstance*](qiskit.utils.QuantumInstance "qiskit.utils.QuantumInstance") *|*[*Backend*](qiskit.providers.Backend "qiskit.providers.Backend") *| None*) – Deprecated: Quantum Instance or Backend
|
||
* **sampler** ([*BaseSampler*](qiskit.primitives.BaseSampler "qiskit.primitives.BaseSampler") *| None*) – A sampler primitive to evaluate the circuits.
|
||
|
||
**Raises**
|
||
|
||
[**ValueError**](https://docs.python.org/3/library/exceptions.html#ValueError "(in Python v3.12)") – If the number of oracle circuits is smaller than 1.
|
||
|
||
## Attributes
|
||
|
||
### quantum\_instance
|
||
|
||
<Attribute id="qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation.quantum_instance">
|
||
Deprecated. Get the quantum instance.
|
||
|
||
<Admonition title="Deprecated since version 0.24.0" type="danger">
|
||
The property `qiskit.algorithms.amplitude_estimators.mlae.MaximumLikelihoodAmplitudeEstimation.quantum_instance` is deprecated as of qiskit-terra 0.24.0. It will be removed no earlier than 3 months after the release date. See [https://qisk.it/algo\_migration](https://qisk.it/algo_migration) for a migration guide.
|
||
</Admonition>
|
||
|
||
**Returns**
|
||
|
||
The quantum instance used to run this algorithm.
|
||
</Attribute>
|
||
|
||
### sampler
|
||
|
||
<Attribute id="qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation.sampler">
|
||
Get the sampler primitive.
|
||
|
||
**Returns**
|
||
|
||
The sampler primitive to evaluate the circuits.
|
||
</Attribute>
|
||
|
||
## Methods
|
||
|
||
### compute\_confidence\_interval
|
||
|
||
<Function id="qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation.compute_confidence_interval" signature="compute_confidence_interval(result, alpha, kind='fisher', apply_post_processing=False)" modifiers="static">
|
||
Compute the alpha confidence interval using the method kind.
|
||
|
||
The confidence level is (1 - alpha) and supported kinds are ‘fisher’, ‘likelihood\_ratio’ and ‘observed\_fisher’ with shorthand notations ‘fi’, ‘lr’ and ‘oi’, respectively.
|
||
|
||
**Parameters**
|
||
|
||
* **result** ([*MaximumLikelihoodAmplitudeEstimationResult*](qiskit.algorithms.MaximumLikelihoodAmplitudeEstimationResult "qiskit.algorithms.amplitude_estimators.mlae.MaximumLikelihoodAmplitudeEstimationResult")) – A maximum likelihood amplitude estimation result.
|
||
* **alpha** ([*float*](https://docs.python.org/3/library/functions.html#float "(in Python v3.12)")) – The confidence level.
|
||
* **kind** ([*str*](https://docs.python.org/3/library/stdtypes.html#str "(in Python v3.12)")) – The method to compute the confidence interval. Defaults to ‘fisher’, which computes the theoretical Fisher information.
|
||
* **apply\_post\_processing** ([*bool*](https://docs.python.org/3/library/functions.html#bool "(in Python v3.12)")) – If True, apply post-processing to the confidence interval.
|
||
|
||
**Returns**
|
||
|
||
The specified confidence interval.
|
||
|
||
**Raises**
|
||
|
||
* [**AlgorithmError**](algorithms#qiskit.algorithms.AlgorithmError "qiskit.algorithms.AlgorithmError") – If run() hasn’t been called yet.
|
||
* [**NotImplementedError**](https://docs.python.org/3/library/exceptions.html#NotImplementedError "(in Python v3.12)") – If the method kind is not supported.
|
||
|
||
**Return type**
|
||
|
||
[tuple](https://docs.python.org/3/library/stdtypes.html#tuple "(in Python v3.12)")\[[float](https://docs.python.org/3/library/functions.html#float "(in Python v3.12)"), [float](https://docs.python.org/3/library/functions.html#float "(in Python v3.12)")]
|
||
</Function>
|
||
|
||
### compute\_mle
|
||
|
||
<Function id="qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation.compute_mle" signature="compute_mle(circuit_results, estimation_problem, num_state_qubits=None, return_counts=False)">
|
||
Compute the MLE via a grid-search.
|
||
|
||
This is a stable approach if sufficient gridpoints are used.
|
||
|
||
**Parameters**
|
||
|
||
* **circuit\_results** ([*list*](https://docs.python.org/3/library/stdtypes.html#list "(in Python v3.12)")*\[*[*dict*](https://docs.python.org/3/library/stdtypes.html#dict "(in Python v3.12)")*\[*[*str*](https://docs.python.org/3/library/stdtypes.html#str "(in Python v3.12)")*,* [*int*](https://docs.python.org/3/library/functions.html#int "(in Python v3.12)")*] | np.ndarray]*) – A list of circuit outcomes. Can be counts or statevectors.
|
||
* **estimation\_problem** ([*EstimationProblem*](qiskit.algorithms.EstimationProblem "qiskit.algorithms.EstimationProblem")) – The estimation problem containing the evaluation schedule and the number of likelihood function evaluations used to find the minimum.
|
||
* **num\_state\_qubits** ([*int*](https://docs.python.org/3/library/functions.html#int "(in Python v3.12)") *| None*) – The number of state qubits, required for statevector simulations.
|
||
* **return\_counts** ([*bool*](https://docs.python.org/3/library/functions.html#bool "(in Python v3.12)")) – If True, returns the good counts.
|
||
|
||
**Returns**
|
||
|
||
The MLE for the provided result object.
|
||
|
||
**Return type**
|
||
|
||
[float](https://docs.python.org/3/library/functions.html#float "(in Python v3.12)") | [tuple](https://docs.python.org/3/library/stdtypes.html#tuple "(in Python v3.12)")\[[float](https://docs.python.org/3/library/functions.html#float "(in Python v3.12)"), [list](https://docs.python.org/3/library/stdtypes.html#list "(in Python v3.12)")\[[float](https://docs.python.org/3/library/functions.html#float "(in Python v3.12)")]]
|
||
</Function>
|
||
|
||
### construct\_circuits
|
||
|
||
<Function id="qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation.construct_circuits" signature="construct_circuits(estimation_problem, measurement=False)">
|
||
Construct the Amplitude Estimation w/o QPE quantum circuits.
|
||
|
||
**Parameters**
|
||
|
||
* **estimation\_problem** ([*EstimationProblem*](qiskit.algorithms.EstimationProblem "qiskit.algorithms.amplitude_estimators.estimation_problem.EstimationProblem")) – The estimation problem for which to construct the QAE circuit.
|
||
* **measurement** ([*bool*](https://docs.python.org/3/library/functions.html#bool "(in Python v3.12)")) – Boolean flag to indicate if measurement should be included in the circuits.
|
||
|
||
**Returns**
|
||
|
||
A list with the QuantumCircuit objects for the algorithm.
|
||
|
||
**Return type**
|
||
|
||
[list](https://docs.python.org/3/library/stdtypes.html#list "(in Python v3.12)")\[[qiskit.circuit.quantumcircuit.QuantumCircuit](qiskit.circuit.QuantumCircuit "qiskit.circuit.quantumcircuit.QuantumCircuit")]
|
||
</Function>
|
||
|
||
### estimate
|
||
|
||
<Function id="qiskit.algorithms.MaximumLikelihoodAmplitudeEstimation.estimate" signature="estimate(estimation_problem)">
|
||
Run the amplitude estimation algorithm on provided estimation problem.
|
||
|
||
**Parameters**
|
||
|
||
**estimation\_problem** ([*EstimationProblem*](qiskit.algorithms.EstimationProblem "qiskit.algorithms.amplitude_estimators.estimation_problem.EstimationProblem")) – The estimation problem.
|
||
|
||
**Returns**
|
||
|
||
An amplitude estimation results object.
|
||
|
||
**Raises**
|
||
|
||
* [**ValueError**](https://docs.python.org/3/library/exceptions.html#ValueError "(in Python v3.12)") – A quantum instance or Sampler must be provided.
|
||
* [**AlgorithmError**](algorithms#qiskit.algorithms.AlgorithmError "qiskit.algorithms.AlgorithmError") – If state\_preparation is not set in estimation\_problem.
|
||
* [**AlgorithmError**](algorithms#qiskit.algorithms.AlgorithmError "qiskit.algorithms.AlgorithmError") – Sampler job run error
|
||
|
||
**Return type**
|
||
|
||
[*MaximumLikelihoodAmplitudeEstimationResult*](qiskit.algorithms.MaximumLikelihoodAmplitudeEstimationResult "qiskit.algorithms.amplitude_estimators.mlae.MaximumLikelihoodAmplitudeEstimationResult")
|
||
</Function>
|
||
</Class>
|
||
|