Naming of QPE and IQPE

.pylintdict

@@ -28,6 +28,7 @@ appfactory
 arcsin
 args
 Armijo
+arxiv
 asmatrix
 assertRaises
 assertEqual
@@ -156,6 +157,7 @@ disp
 distro
 dj
 dnf
+Dobsicek
 docplex
 docplex's
 Docplex

qiskit/aqua/algorithms/__init__.py

@@ -169,10 +169,10 @@
    :nosignatures:
 
    ClassicalCPLEX
-   IQPEMinimumEigensolver
+   IQPE
    NumPyMinimumEigensolver
    QAOA
-   QPEMinimumEigensolver
+   QPE
    VQE
 
 """
@@ -190,8 +190,7 @@
 from .eigen_solvers import NumPyEigensolver, ExactEigensolver, EigensolverResult
 from .factorizers import Shor
 from .linear_solvers import HHL, NumPyLSsolver, ExactLSsolver
-from .minimum_eigen_solvers import (VQE, VQEResult, QAOA, IQPE, IQPEMinimumEigensolver, IQPEResult,
-                                    QPE, QPEMinimumEigensolver, QPEResult,
+from .minimum_eigen_solvers import (VQE, VQEResult, QAOA, IQPE, IQPEResult, QPE, QPEResult,
                                     ClassicalCPLEX, CPLEX_Ising, NumPyMinimumEigensolver,
                                     MinimumEigensolver, MinimumEigensolverResult)
 from .education import EOH, Simon, DeutschJozsa, BernsteinVazirani
@@ -223,10 +222,8 @@
     'QSVM',
     'Grover',
     'IQPE',
-    'IQPEMinimumEigensolver',
     'IQPEResult',
     'QPE',
-    'QPEMinimumEigensolver',
     'QPEResult',
     'AmplitudeEstimation',
     'IterativeAmplitudeEstimation',

qiskit/aqua/algorithms/minimum_eigen_solvers/__init__.py

@@ -16,8 +16,8 @@
 
 from .vqe import VQE, VQEResult
 from .qaoa import QAOA
-from .iqpe import IQPE, IQPEMinimumEigensolver, IQPEResult
-from .qpe import QPE, QPEMinimumEigensolver, QPEResult
+from .iqpe import IQPE, IQPEResult
+from .qpe import QPE, QPEResult
 from .cplex import ClassicalCPLEX, CPLEX_Ising
 from .numpy_minimum_eigen_solver import NumPyMinimumEigensolver
 from .minimum_eigen_solver import MinimumEigensolver, MinimumEigensolverResult
@@ -27,10 +27,8 @@
     'VQEResult',
     'QAOA',
     'IQPE',
-    'IQPEMinimumEigensolver',
     'IQPEResult',
     'QPE',
-    'QPEMinimumEigensolver',
     'QPEResult',
     'ClassicalCPLEX',
     'CPLEX_Ising',

qiskit/aqua/algorithms/minimum_eigen_solvers/iqpe.py

@@ -11,14 +11,14 @@
 # Any modifications or derivative works of this code must retain this
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
-"""
-The Iterative Quantum Phase Estimation Algorithm.
+
+"""The Iterative Quantum Phase Estimation Algorithm.
+
 See https://arxiv.org/abs/quant-ph/0610214
 """
 
 from typing import Optional, List, Dict, Union
 import logging
-import warnings
 import numpy as np
 
 from qiskit import QuantumRegister, ClassicalRegister, QuantumCircuit
@@ -42,16 +42,18 @@
 # pylint: disable=invalid-name
 
 
-class IQPEMinimumEigensolver(QuantumAlgorithm, MinimumEigensolver):
-    """
-    The Iterative Quantum Phase Estimation algorithm.
+class IQPE(QuantumAlgorithm, MinimumEigensolver):
+    """The Iterative Quantum Phase Estimation algorithm.
 
     IQPE, as its name suggests, iteratively computes the phase so as to require fewer qubits.
     It takes has the same set of parameters as :class:`QPE`, except for the number of
     ancillary qubits *num_ancillae*, being replaced by *num_iterations* and that
     an Inverse Quantum Fourier Transform (IQFT) is not used for IQPE.
 
-    See also https://arxiv.org/abs/quant-ph/0610214
+    **Reference:**
+
+    [1]: Dobsicek et al. (2006), Arbitrary accuracy iterative phase estimation algorithm as a two
+       qubit benchmark, `arxiv/quant-ph/0610214 <https://arxiv.org/abs/quant-ph/0610214>`_
     """
 
     def __init__(self,
@@ -308,28 +310,6 @@ def _run(self) -> 'IQPEResult':
         return result
 
 
-class IQPE(IQPEMinimumEigensolver):
-    """
-    The deprecated Iterative Quantum Phase Estimation algorithm.
-    """
-
-    def __init__(self,
-                 operator: Optional[LegacyBaseOperator] = None,
-                 state_in: Optional[InitialState] = None,
-                 num_time_slices: int = 1,
-                 num_iterations: int = 1,
-                 expansion_mode: str = 'suzuki',
-                 expansion_order: int = 2,
-                 shallow_circuit_concat: bool = False) -> None:
-        warnings.warn('Deprecated class {}, use {}.'.format('IQPE',
-                                                            'IQPEMinimumEigenSolver'),
-                      DeprecationWarning)
-        super().__init__(operator, state_in,
-                         num_time_slices, num_iterations,
-                         expansion_mode, expansion_order,
-                         shallow_circuit_concat)
-
-
 class IQPEResult(QPEResult):
     """ IQPE Result."""
 

qiskit/aqua/algorithms/minimum_eigen_solvers/qpe.py

@@ -41,7 +41,7 @@
 # pylint: disable=invalid-name
 
 
-class QPEMinimumEigensolver(QuantumAlgorithm, MinimumEigensolver):
+class QPE(QuantumAlgorithm, MinimumEigensolver):
     """The Quantum Phase Estimation algorithm.
 
     QPE (also sometimes abbreviated as PEA, for Phase Estimation Algorithm), has two quantum
@@ -248,28 +248,6 @@ def _run(self) -> 'QPEResult':
         return result
 
 
-class QPE(QPEMinimumEigensolver):
-    """
-    The deprecated Quantum Phase Estimation algorithm.
-    """
-
-    def __init__(self,
-                 operator: Optional[LegacyBaseOperator] = None,
-                 state_in: Optional[InitialState] = None,
-                 iqft: Optional[IQFT] = None,
-                 num_time_slices: int = 1,
-                 num_ancillae: int = 1,
-                 expansion_mode: str = 'trotter',
-                 expansion_order: int = 1,
-                 shallow_circuit_concat: bool = False) -> None:
-        warnings.warn('Deprecated class {}, use {}.'.format('QPE',
-                                                            'QPEMinimumEigenSolver'),
-                      DeprecationWarning)
-        super().__init__(operator, state_in, iqft,
-                         num_time_slices, num_ancillae, expansion_mode,
-                         expansion_order, shallow_circuit_concat)
-
-
 class QPEResult(MinimumEigensolverResult):
     """ QPE Result."""
 

test/aqua/test_iqpe.py

@@ -21,7 +21,7 @@
 from qiskit import BasicAer
 from qiskit.aqua import QuantumInstance
 from qiskit.aqua.utils import decimal_to_binary
-from qiskit.aqua.algorithms import IQPEMinimumEigensolver
+from qiskit.aqua.algorithms import IQPE
 from qiskit.aqua.algorithms import NumPyMinimumEigensolver
 from qiskit.aqua.operators import WeightedPauliOperator, MatrixOperator
 from qiskit.aqua.operators.legacy import op_converter
@@ -87,9 +87,9 @@ def test_iqpe(self, qubit_op, simulator, num_time_slices, num_iterations):
         self.log.debug('The corresponding eigenvector: %s', ref_eigenvec)
 
         state_in = Custom(qubit_op.num_qubits, state_vector=ref_eigenvec)
-        iqpe = IQPEMinimumEigensolver(qubit_op, state_in, num_time_slices, num_iterations,
-                                      expansion_mode='suzuki', expansion_order=2,
-                                      shallow_circuit_concat=True)
+        iqpe = IQPE(qubit_op, state_in, num_time_slices, num_iterations,
+                    expansion_mode='suzuki', expansion_order=2,
+                    shallow_circuit_concat=True)
 
         backend = BasicAer.get_backend(simulator)
         quantum_instance = QuantumInstance(backend, shots=100)

test/aqua/test_qpe.py

@@ -25,7 +25,7 @@
 from qiskit.aqua.operators.legacy import op_converter
 from qiskit.aqua.utils import decimal_to_binary
 from qiskit.aqua.algorithms import NumPyMinimumEigensolver
-from qiskit.aqua.algorithms import QPEMinimumEigensolver
+from qiskit.aqua.algorithms import QPE
 from qiskit.circuit.library import QFT
 from qiskit.aqua.components.iqfts import Standard
 from qiskit.aqua.components.initial_states import Custom
@@ -105,9 +105,9 @@ def test_qpe(self, qubit_op, simulator, num_time_slices, n_ancillae, use_circuit
             warnings.filterwarnings(action="ignore", category=DeprecationWarning)
             iqft = Standard(n_ancillae)
 
-        qpe = QPEMinimumEigensolver(qubit_op, state_in, iqft, num_time_slices, n_ancillae,
-                                    expansion_mode='suzuki', expansion_order=2,
-                                    shallow_circuit_concat=True)
+        qpe = QPE(qubit_op, state_in, iqft, num_time_slices, n_ancillae,
+                  expansion_mode='suzuki', expansion_order=2,
+                  shallow_circuit_concat=True)
 
         backend = BasicAer.get_backend(simulator)
         quantum_instance = QuantumInstance(backend, shots=100)

test/aqua/test_vqe2iqpe.py

@@ -27,7 +27,7 @@
 from qiskit.aqua.components.variational_forms import RYRZ
 from qiskit.aqua.components.optimizers import SPSA
 from qiskit.aqua.algorithms import VQE
-from qiskit.aqua.algorithms import IQPEMinimumEigensolver
+from qiskit.aqua.algorithms import IQPE
 
 
 class TestVQE2IQPE(QiskitAquaTestCase):
@@ -67,9 +67,9 @@ def test_vqe_2_iqpe(self):
         num_iterations = 6
 
         state_in = VarFormBased(var_form, result.optimal_point)
-        iqpe = IQPEMinimumEigensolver(self.qubit_op, state_in, num_time_slices, num_iterations,
-                                      expansion_mode='suzuki', expansion_order=2,
-                                      shallow_circuit_concat=True)
+        iqpe = IQPE(self.qubit_op, state_in, num_time_slices, num_iterations,
+                    expansion_mode='suzuki', expansion_order=2,
+                    shallow_circuit_concat=True)
         quantum_instance = QuantumInstance(
             backend, shots=100, seed_transpiler=self.seed, seed_simulator=self.seed
         )

test/chemistry/test_app_mgse.py

@@ -21,7 +21,7 @@
 
 from qiskit import BasicAer
 from qiskit.aqua import QuantumInstance
-from qiskit.aqua.algorithms import NumPyMinimumEigensolver, VQE, IQPEMinimumEigensolver
+from qiskit.aqua.algorithms import NumPyMinimumEigensolver, VQE, IQPE
 from qiskit.aqua.components.optimizers import SLSQP
 from qiskit.aqua.components.variational_forms import RY
 from qiskit.chemistry import QiskitChemistryError
@@ -101,9 +101,9 @@ def cb_create_solver(num_particles, num_orbitals,
                              qubit_mapping, two_qubit_reduction, z2_symmetries):
             state_in = HartreeFock(2, num_orbitals, num_particles, qubit_mapping,
                                    two_qubit_reduction, z2_symmetries.sq_list)
-            iqpe = IQPEMinimumEigensolver(None, state_in, num_time_slices=1, num_iterations=6,
-                                          expansion_mode='suzuki', expansion_order=2,
-                                          shallow_circuit_concat=True)
+            iqpe = IQPE(None, state_in, num_time_slices=1, num_iterations=6,
+                        expansion_mode='suzuki', expansion_order=2,
+                        shallow_circuit_concat=True)
             iqpe.quantum_instance = QuantumInstance(BasicAer.get_backend('qasm_simulator'),
                                                     shots=100)
             return iqpe

test/chemistry/test_end2end_with_iqpe.py

@@ -21,7 +21,7 @@
 import qiskit
 from qiskit.aqua.utils import decimal_to_binary
 from qiskit.aqua import QuantumInstance
-from qiskit.aqua.algorithms import IQPEMinimumEigensolver, NumPyMinimumEigensolver
+from qiskit.aqua.algorithms import IQPE, NumPyMinimumEigensolver
 from qiskit.aqua.operators import Z2Symmetries
 from qiskit.chemistry.drivers import PySCFDriver, UnitsType
 from qiskit.chemistry import FermionicOperator, QiskitChemistryError
@@ -70,9 +70,9 @@ def test_iqpe(self, distance):
         num_iterations = 6
         state_in = HartreeFock(qubit_op.num_qubits, num_orbitals,
                                num_particles, qubit_mapping, two_qubit_reduction)
-        iqpe = IQPEMinimumEigensolver(qubit_op, state_in, num_time_slices, num_iterations,
-                                      expansion_mode='suzuki', expansion_order=2,
-                                      shallow_circuit_concat=True)
+        iqpe = IQPE(qubit_op, state_in, num_time_slices, num_iterations,
+                    expansion_mode='suzuki', expansion_order=2,
+                    shallow_circuit_concat=True)
         backend = qiskit.BasicAer.get_backend('qasm_simulator')
         quantum_instance = QuantumInstance(backend, shots=100)
 

test/chemistry/test_end2end_with_qpe.py

@@ -24,7 +24,7 @@
 from qiskit.circuit.library import QFT
 from qiskit.aqua.utils import decimal_to_binary
 from qiskit.aqua import QuantumInstance
-from qiskit.aqua.algorithms import QPEMinimumEigensolver, NumPyMinimumEigensolver
+from qiskit.aqua.algorithms import QPE, NumPyMinimumEigensolver
 from qiskit.aqua.components.iqfts import Standard
 from qiskit.aqua.operators import Z2Symmetries
 from qiskit.chemistry.drivers import PySCFDriver, UnitsType
@@ -88,9 +88,9 @@ def test_qpe(self, distance, use_circuit_library):
         else:
             iqft = Standard(n_ancillae)
 
-        qpe = QPEMinimumEigensolver(qubit_op, state_in, iqft, num_time_slices, n_ancillae,
-                                    expansion_mode='suzuki',
-                                    expansion_order=2, shallow_circuit_concat=True)
+        qpe = QPE(qubit_op, state_in, iqft, num_time_slices, n_ancillae,
+                  expansion_mode='suzuki',
+                  expansion_order=2, shallow_circuit_concat=True)
         backend = qiskit.BasicAer.get_backend('qasm_simulator')
         quantum_instance = QuantumInstance(backend, shots=100)
         result = qpe.run(quantum_instance)