Rewrite Amplitude Estimators with Primitives

Qiskit · Aug 31, 2022 · d7dd578 · d7dd578
1 parent 69ad6c6
commit d7dd578
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Showing 4 changed files with 121 additions and 17 deletions.
diff --git a/qiskit/algorithms/amplitude_estimators/ae.py b/qiskit/algorithms/amplitude_estimators/ae.py
@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2018, 2020.
+# (C) Copyright IBM 2018, 2022.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -14,13 +14,16 @@
 
 from typing import Optional, Union, List, Tuple, Dict
 from collections import OrderedDict
+import warnings
 import numpy as np
 from scipy.stats import chi2, norm
 from scipy.optimize import bisect
 
 from qiskit import QuantumCircuit, ClassicalRegister
 from qiskit.providers import Backend
+from qiskit.primitives import BaseSampler
 from qiskit.utils import QuantumInstance
+from qiskit.utils.deprecation import deprecate_function
 from .amplitude_estimator import AmplitudeEstimator, AmplitudeEstimatorResult
 from .ae_utils import pdf_a, derivative_log_pdf_a, bisect_max
 from .estimation_problem import EstimationProblem
@@ -59,6 +62,7 @@ def __init__(
         phase_estimation_circuit: Optional[QuantumCircuit] = None,
         iqft: Optional[QuantumCircuit] = None,
         quantum_instance: Optional[Union[QuantumInstance, Backend]] = None,
+        sampler: Optional[BaseSampler] = None,
     ) -> None:
         r"""
         Args:
@@ -68,7 +72,9 @@ def __init__(
                 `qiskit.circuit.library.PhaseEstimation` when None.
             iqft: The inverse quantum Fourier transform component, defaults to using a standard
                 implementation from `qiskit.circuit.library.QFT` when None.
-            quantum_instance: The backend (or `QuantumInstance`) to execute the circuits on.
+            quantum_instance: Pending deprecation\: The backend (or `QuantumInstance`) to execute
+                the circuits on.
+            sampler: base sampler
 
         Raises:
             ValueError: If the number of evaluation qubits is smaller than 1.
@@ -79,6 +85,13 @@ def __init__(
         super().__init__()
 
         # set quantum instance
+        if quantum_instance is not None:
+            warnings.warn(
+                "The quantum_instance argument has been superseded by the sampler argument. "
+                "This argument will be deprecated in a future release and subsequently "
+                "removed after that.",
+                category=PendingDeprecationWarning,
+            )
         self.quantum_instance = quantum_instance
 
         # get parameters
@@ -87,19 +100,32 @@ def __init__(
 
         self._iqft = iqft
         self._pec = phase_estimation_circuit
+        self._sampler = sampler
 
     @property
+    @deprecate_function(
+        "The AmplitudeEstimation.quantum_instance getter is pending deprecation. "
+        "This property will be deprecated in a future release and subsequently "
+        "removed after that.",
+        category=PendingDeprecationWarning,
+    )
     def quantum_instance(self) -> Optional[QuantumInstance]:
-        """Get the quantum instance.
+        """Pending deprecation: Get the quantum instance.
 
         Returns:
             The quantum instance used to run this algorithm.
         """
         return self._quantum_instance
 
     @quantum_instance.setter
+    @deprecate_function(
+        "The AmplitudeEstimation.quantum_instance setter is pending deprecation. "
+        "This property will be deprecated in a future release and subsequently "
+        "removed after that.",
+        category=PendingDeprecationWarning,
+    )
     def quantum_instance(self, quantum_instance: Union[QuantumInstance, Backend]) -> None:
-        """Set quantum instance.
+        """Pending deprecation: Set quantum instance.
 
         Args:
             quantum_instance: The quantum instance used to run this algorithm.

diff --git a/qiskit/algorithms/amplitude_estimators/fae.py b/qiskit/algorithms/amplitude_estimators/fae.py
@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2017, 2020.
+# (C) Copyright IBM 2017, 2022.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -13,11 +13,14 @@
 """Faster Amplitude Estimation."""
 
 from typing import Optional, Union, List, Tuple
+import warnings
 import numpy as np
 
 from qiskit.circuit import QuantumCircuit, ClassicalRegister
 from qiskit.providers import Backend
+from qiskit.primitives import BaseSampler
 from qiskit.utils import QuantumInstance
+from qiskit.utils.deprecation import deprecate_function
 from qiskit.algorithms.exceptions import AlgorithmError
 
 from .amplitude_estimator import AmplitudeEstimator, AmplitudeEstimatorResult
@@ -51,13 +54,16 @@ def __init__(
         maxiter: int,
         rescale: bool = True,
         quantum_instance: Optional[Union[QuantumInstance, Backend]] = None,
+        sampler: Optional[BaseSampler] = None,
     ) -> None:
         r"""
         Args:
             delta: The probability that the true value is outside of the final confidence interval.
             maxiter: The number of iterations, the maximal power of Q is `2 ** (maxiter - 1)`.
             rescale: Whether to rescale the problem passed to `estimate`.
-            quantum_instance: The quantum instance or backend to run the circuits.
+            quantum_instance: Pending deprecation\: The quantum instance or backend
+                to run the circuits.
+            sampler: base sampler
 
         .. note::
 
@@ -66,25 +72,46 @@ def __init__(
 
         """
         super().__init__()
+        # set quantum instance
+        if quantum_instance is not None:
+            warnings.warn(
+                "The quantum_instance argument has been superseded by the sampler argument. "
+                "This argument will be deprecated in a future release and subsequently "
+                "removed after that.",
+                category=PendingDeprecationWarning,
+            )
         self.quantum_instance = quantum_instance
         self._shots = (int(1944 * np.log(2 / delta)), int(972 * np.log(2 / delta)))
         self._rescale = rescale
         self._delta = delta
         self._maxiter = maxiter
         self._num_oracle_calls = 0
+        self._sampler = sampler
 
     @property
+    @deprecate_function(
+        "The FasterAmplitudeEstimation.quantum_instance getter is pending deprecation. "
+        "This property will be deprecated in a future release and subsequently "
+        "removed after that.",
+        category=PendingDeprecationWarning,
+    )
     def quantum_instance(self) -> Optional[QuantumInstance]:
-        """Get the quantum instance.
+        """Pending deprecation: Get the quantum instance.
 
         Returns:
             The quantum instance used to run this algorithm.
         """
         return self._quantum_instance
 
     @quantum_instance.setter
+    @deprecate_function(
+        "The FasterAmplitudeEstimation.quantum_instance setter is pending deprecation. "
+        "This property will be deprecated in a future release and subsequently "
+        "removed after that.",
+        category=PendingDeprecationWarning,
+    )
     def quantum_instance(self, quantum_instance: Union[QuantumInstance, Backend]) -> None:
-        """Set quantum instance.
+        """Pending deprecation: Set quantum instance.
 
         Args:
             quantum_instance: The quantum instance used to run this algorithm.

diff --git a/qiskit/algorithms/amplitude_estimators/iae.py b/qiskit/algorithms/amplitude_estimators/iae.py
@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2018, 2020.
+# (C) Copyright IBM 2018, 2022.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -13,12 +13,15 @@
 """The Iterative Quantum Amplitude Estimation Algorithm."""
 
 from typing import Optional, Union, List, Tuple, Dict, cast
+import warnings
 import numpy as np
 from scipy.stats import beta
 
 from qiskit import ClassicalRegister, QuantumCircuit
 from qiskit.providers import Backend
+from qiskit.primitives import BaseSampler
 from qiskit.utils import QuantumInstance
+from qiskit.utils.deprecation import deprecate_function
 
 from .amplitude_estimator import AmplitudeEstimator, AmplitudeEstimatorResult
 from .estimation_problem import EstimationProblem
@@ -53,6 +56,7 @@ def __init__(
         confint_method: str = "beta",
         min_ratio: float = 2,
         quantum_instance: Optional[Union[QuantumInstance, Backend]] = None,
+        sampler: Optional[BaseSampler] = None,
     ) -> None:
         r"""
         The output of the algorithm is an estimate for the amplitude `a`, that with at least
@@ -66,7 +70,8 @@ def __init__(
                 each iteration, can be 'chernoff' for the Chernoff intervals or 'beta' for the
                 Clopper-Pearson intervals (default)
             min_ratio: Minimal q-ratio (:math:`K_{i+1} / K_i`) for FindNextK
-            quantum_instance: Quantum Instance or Backend
+            quantum_instance: Pending deprecation\: Quantum Instance or Backend
+            sampler: base sampler
 
         Raises:
             AlgorithmError: if the method to compute the confidence intervals is not supported
@@ -89,26 +94,46 @@ def __init__(
         super().__init__()
 
         # set quantum instance
+        if quantum_instance is not None:
+            warnings.warn(
+                "The quantum_instance argument has been superseded by the sampler argument. "
+                "This argument will be deprecated in a future release and subsequently "
+                "removed after that.",
+                category=PendingDeprecationWarning,
+            )
         self.quantum_instance = quantum_instance
 
         # store parameters
         self._epsilon = epsilon_target
         self._alpha = alpha
         self._min_ratio = min_ratio
         self._confint_method = confint_method
+        self._sampler = sampler
 
     @property
+    @deprecate_function(
+        "The IterativeAmplitudeEstimation.quantum_instance getter is pending deprecation. "
+        "This property will be deprecated in a future release and subsequently "
+        "removed after that.",
+        category=PendingDeprecationWarning,
+    )
     def quantum_instance(self) -> Optional[QuantumInstance]:
-        """Get the quantum instance.
+        """Pending deprecation: Get the quantum instance.
 
         Returns:
             The quantum instance used to run this algorithm.
         """
         return self._quantum_instance
 
     @quantum_instance.setter
+    @deprecate_function(
+        "The IterativeAmplitudeEstimation.quantum_instance setter is pending deprecation. "
+        "This property will be deprecated in a future release and subsequently "
+        "removed after that.",
+        category=PendingDeprecationWarning,
+    )
     def quantum_instance(self, quantum_instance: Union[QuantumInstance, Backend]) -> None:
-        """Set quantum instance.
+        """Pending deprecation: Set quantum instance.
 
         Args:
             quantum_instance: The quantum instance used to run this algorithm.

diff --git a/qiskit/algorithms/amplitude_estimators/mlae.py b/qiskit/algorithms/amplitude_estimators/mlae.py
@@ -1,6 +1,6 @@
 # This code is part of Qiskit.
 #
-# (C) Copyright IBM 2018, 2020.
+# (C) Copyright IBM 2018, 2022.
 #
 # This code is licensed under the Apache License, Version 2.0. You may
 # obtain a copy of this license in the LICENSE.txt file in the root directory
@@ -13,13 +13,16 @@
 """The Maximum Likelihood Amplitude Estimation algorithm."""
 
 from typing import Optional, List, Union, Tuple, Dict, Callable
+import warnings
 import numpy as np
 from scipy.optimize import brute
 from scipy.stats import norm, chi2
 
 from qiskit.providers import Backend
 from qiskit import ClassicalRegister, QuantumRegister, QuantumCircuit
 from qiskit.utils import QuantumInstance
+from qiskit.primitives import BaseSampler
+from qiskit.utils.deprecation import deprecate_function
 
 from .amplitude_estimator import AmplitudeEstimator, AmplitudeEstimatorResult
 from .estimation_problem import EstimationProblem
@@ -52,6 +55,7 @@ def __init__(
         evaluation_schedule: Union[List[int], int],
         minimizer: Optional[MINIMIZER] = None,
         quantum_instance: Optional[Union[QuantumInstance, Backend]] = None,
+        sampler: Optional[BaseSampler] = None,
     ) -> None:
         r"""
         Args:
@@ -64,7 +68,8 @@ def __init__(
                 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: Quantum Instance or Backend
+            quantum_instance: Pending deprecation\: Quantum Instance or Backend
+            sampler: base sampler
 
         Raises:
             ValueError: If the number of oracle circuits is smaller than 1.
@@ -73,6 +78,13 @@ def __init__(
         super().__init__()
 
         # set quantum instance
+        if quantum_instance is not None:
+            warnings.warn(
+                "The quantum_instance argument has been superseded by the sampler argument. "
+                "This argument will be deprecated in a future release and subsequently "
+                "removed after that.",
+                category=PendingDeprecationWarning,
+            )
         self.quantum_instance = quantum_instance
 
         # get parameters
@@ -98,18 +110,32 @@ def default_minimizer(objective_fn, bounds):
         else:
             self._minimizer = minimizer
 
+        self._sampler = sampler
+
     @property
+    @deprecate_function(
+        "The MaximumLikelihoodAmplitudeEstimation.quantum_instance getter is pending deprecation. "
+        "This property will be deprecated in a future release and subsequently "
+        "removed after that.",
+        category=PendingDeprecationWarning,
+    )
     def quantum_instance(self) -> Optional[QuantumInstance]:
-        """Get the quantum instance.
+        """Pending deprecation: Get the quantum instance.
 
         Returns:
             The quantum instance used to run this algorithm.
         """
         return self._quantum_instance
 
     @quantum_instance.setter
+    @deprecate_function(
+        "The MaximumLikelihoodAmplitudeEstimation.quantum_instance setter is pending deprecation. "
+        "This property will be deprecated in a future release and subsequently "
+        "removed after that.",
+        category=PendingDeprecationWarning,
+    )
     def quantum_instance(self, quantum_instance: Union[QuantumInstance, Backend]) -> None:
-        """Set quantum instance.
+        """Pending deprecation: Set quantum instance.
 
         Args:
             quantum_instance: The quantum instance used to run this algorithm.
@@ -148,7 +174,7 @@ def construct_circuits(
         qc_0.compose(estimation_problem.state_preparation, inplace=True)
 
         for k in self._evaluation_schedule:
-            qc_k = qc_0.copy(name="qc_a_q_%s" % k)
+            qc_k = qc_0.copy(name=f"qc_a_q_{k}")
 
             if k != 0:
                 qc_k.compose(estimation_problem.grover_operator.power(k), inplace=True)