Add instructions to set simulator state (#1163)

Qiskit · Mar 26, 2021 · 25a6d91 · 25a6d91
1 parent 4f615be
commit 25a6d91
Show file tree

Hide file tree

Showing 43 changed files with 972 additions and 167 deletions.
diff --git a/qiskit/providers/aer/backends/qasm_simulator.py b/qiskit/providers/aer/backends/qasm_simulator.py
@@ -288,7 +288,8 @@ class QasmSimulator(AerBackend):
         'save_probabilities', 'save_probabilities_dict',
         'save_amplitudes', 'save_amplitudes_sq', 'save_state',
         'save_density_matrix', 'save_statevector', 'save_statevector_dict',
-        'save_stabilizer'
+        'save_stabilizer', 'set_statevector', 'set_density_matrix',
+        'set_stabilizer'
     ])
 
     _DEFAULT_CONFIGURATION = {
@@ -560,15 +561,25 @@ def _method_basis_gates(self):
 
     def _custom_instructions(self):
         """Return method basis gates and custom instructions"""
+        # pylint: disable = too-many-return-statements
         if 'custom_instructions' in self._options_configuration:
             return self._options_configuration['custom_instructions']
 
         method = self._options.get('method', None)
+        if method in ['statevector', 'statevector_gpu', 'statevector_thrust']:
+            return sorted([
+                'roerror', 'kraus', 'snapshot', 'save_expval', 'save_expval_var',
+                'save_probabilities', 'save_probabilities_dict',
+                'save_amplitudes', 'save_amplitudes_sq', 'save_state',
+                'save_density_matrix', 'save_statevector', 'save_statevector_dict',
+                'set_statevector'
+            ])
         if method in ['density_matrix', 'density_matrix_gpu', 'density_matrix_thrust']:
             return sorted([
                 'roerror', 'kraus', 'superop', 'snapshot', 'save_expval', 'save_expval_var',
                 'save_probabilities', 'save_probabilities_dict',
-                'save_state', 'save_density_matrix', 'save_amplitudes_sq'
+                'save_state', 'save_density_matrix', 'save_amplitudes_sq',
+                'set_statevector', 'set_density_matrix'
             ])
         if method == 'matrix_product_state':
             return sorted([
@@ -580,7 +591,8 @@ def _custom_instructions(self):
             return sorted([
                 'roerror', 'snapshot', 'save_expval', 'save_expval_var',
                 'save_probabilities', 'save_probabilities_dict',
-                'save_amplitudes_sq', 'save_state', 'save_stabilizer'
+                'save_amplitudes_sq', 'save_state', 'save_stabilizer',
+                'set_stabilizer'
             ])
         if method == 'extended_stabilizer':
             return sorted(['roerror', 'snapshot', 'save_statevector',

diff --git a/qiskit/providers/aer/backends/statevector_simulator.py b/qiskit/providers/aer/backends/statevector_simulator.py
@@ -134,7 +134,7 @@ class StatevectorSimulator(AerBackend):
             'kraus', 'roerror',
             'save_expval', 'save_density_matrix', 'save_statevector',
             'save_probs', 'save_probs_ket', 'save_amplitudes',
-            'save_amplitudes_sq', 'save_state'
+            'save_amplitudes_sq', 'save_state', 'set_statevector'
         ]),
         'gates': []
     }

diff --git a/qiskit/providers/aer/backends/unitary_simulator.py b/qiskit/providers/aer/backends/unitary_simulator.py
@@ -135,7 +135,7 @@ class UnitarySimulator(AerBackend):
             'mcp', 'mcu1', 'mcu2', 'mcu3', 'mcrx', 'mcry', 'mcrz',
             'mcr', 'mcswap', 'unitary', 'diagonal', 'multiplexer', 'delay', 'pauli',
         ]),
-        'custom_instructions': sorted(['save_unitary', 'save_state']),
+        'custom_instructions': sorted(['save_unitary', 'save_state', 'set_unitary']),
         'gates': []
     }
 

diff --git a/qiskit/providers/aer/library/__init__.py b/qiskit/providers/aer/library/__init__.py
@@ -9,7 +9,6 @@
 # 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.
-
 """
 =========================================================
 Instruction Library (:mod:`qiskit.providers.aer.library`)
@@ -21,6 +20,39 @@
 :class:`~qiskit.circuit.Instruction` subclasses that can be used
 with the Aer circuit simulator backends.
 
+Setting a Custom Simulator State
+================================
+
+The following instruction classes can be used to set the specific
+simulator methods to a custom state. Note that these instructions
+are only valid when applied to all qubits in a circuit. Applying
+to a subset of qubits will raise an exception during execution.
+
+Instruction Classes
+-------------------
+
+.. autosummary::
+    :toctree: ../stubs/
+
+    SetStatevector
+    SetDensityMatrix
+    SetStabilizer
+    SetUnitary
+
+Then can also be used using custom QuantumCircuit methods
+
+QuantumCircuit Methods
+----------------------
+
+.. autosummary::
+    :toctree: ../stubs/
+
+    set_statevector
+    set_density_matrix
+    set_stabilizer
+    set_unitary
+
+
 Saving Simulator Data
 =====================
 
@@ -99,24 +131,21 @@
     state.
 """
 
-__all__ = ['SaveState',
-           'SaveExpectationValue', 'SaveExpectationValueVariance',
-           'SaveProbabilities', 'SaveProbabilitiesDict',
-           'SaveStatevector', 'SaveStatevectorDict', 'SaveDensityMatrix',
-           'SaveAmplitudes', 'SaveAmplitudesSquared', 'SaveUnitary',
-           'SaveStabilizer', 'SaveMatrixProductState']
-
-from .save_state import SaveState, save_state
-from .save_expectation_value import (
-    SaveExpectationValue, save_expectation_value,
-    SaveExpectationValueVariance, save_expectation_value_variance)
-from .save_probabilities import (SaveProbabilities, save_probabilities,
-                                 SaveProbabilitiesDict, save_probabilities_dict)
-from .save_statevector import (SaveStatevector, save_statevector,
-                               SaveStatevectorDict, save_statevector_dict)
-from .save_density_matrix import SaveDensityMatrix, save_density_matrix
-from .save_amplitudes import (SaveAmplitudes, save_amplitudes,
-                              SaveAmplitudesSquared, save_amplitudes_squared)
-from .save_stabilizer import SaveStabilizer, save_stabilizer
-from .save_unitary import SaveUnitary, save_unitary
-from .save_matrix_product_state import SaveMatrixProductState, save_matrix_product_state
+__all__ = [
+    'SaveState',
+    'SaveExpectationValue',
+    'SaveExpectationValueVariance',
+    'SaveProbabilities',
+    'SaveProbabilitiesDict',
+    'SaveStatevector',
+    'SaveStatevectorDict',
+    'SaveDensityMatrix',
+    'SaveAmplitudes',
+    'SaveAmplitudesSquared',
+    'SaveUnitary',
+    'SaveStabilizer',
+    'SaveMatrixProductState'
+]
+
+from .save_instructions import *
+from .set_instructions import *
diff --git a/qiskit/providers/aer/library/default_qubits.py b/qiskit/providers/aer/library/default_qubits.py
@@ -0,0 +1,55 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2018, 2021.
+#
+# 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
+# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
+#
+# 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.
+"""
+Helper function
+"""
+
+from qiskit.circuit import QuantumCircuit, QuantumRegister
+from qiskit.extensions.exceptions import ExtensionError
+
+
+def default_qubits(circuit, qubits=None):
+    """Helper method to return list of qubits.
+
+    Args:
+        circuit (QuantumCircuit): a quantum circuit.
+        qubits (list or QuantumRegister): Optional, qubits argument,
+            If None the returned list will be all qubits in the circuit.
+            [Default: None]
+
+    Raises:
+            ExtensionError: if default qubits fails.
+
+    Returns:
+        list: qubits list.
+    """
+    # Convert label to string for backwards compatibility
+    # If no qubits are specified we add all qubits so it acts as a barrier
+    # This is needed for full register snapshots like statevector
+    if isinstance(qubits, QuantumRegister):
+        qubits = qubits[:]
+    if not qubits:
+        tuples = []
+        if isinstance(circuit, QuantumCircuit):
+            for register in circuit.qregs:
+                tuples.append(register)
+        if not tuples:
+            raise ExtensionError('no qubits for snapshot')
+        qubits = []
+        for tuple_element in tuples:
+            if isinstance(tuple_element, QuantumRegister):
+                for j in range(tuple_element.size):
+                    qubits.append(tuple_element[j])
+            else:
+                qubits.append(tuple_element)
+
+    return qubits
diff --git a/qiskit/providers/aer/library/save_instructions/__init__.py b/qiskit/providers/aer/library/save_instructions/__init__.py
@@ -0,0 +1,30 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2018, 2021.
+#
+# 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
+# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
+#
+# 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.
+"""Save directive instructions for the Aer simulator"""
+
+from .save_state import (SaveState, save_state)
+from .save_expectation_value import (SaveExpectationValue,
+                                     save_expectation_value,
+                                     SaveExpectationValueVariance,
+                                     save_expectation_value_variance)
+from .save_probabilities import (SaveProbabilities, save_probabilities,
+                                 SaveProbabilitiesDict,
+                                 save_probabilities_dict)
+from .save_statevector import (SaveStatevector, save_statevector,
+                               SaveStatevectorDict, save_statevector_dict)
+from .save_density_matrix import SaveDensityMatrix, save_density_matrix
+from .save_amplitudes import (SaveAmplitudes, save_amplitudes,
+                              SaveAmplitudesSquared, save_amplitudes_squared)
+from .save_stabilizer import (SaveStabilizer, save_stabilizer)
+from .save_unitary import (SaveUnitary, save_unitary)
+from .save_matrix_product_state import (
+    SaveMatrixProductState, save_matrix_product_state)
diff --git a/.../providers/aer/library/save_amplitudes.py → ...rary/save_instructions/save_amplitudes.py b/.../providers/aer/library/save_amplitudes.py → ...rary/save_instructions/save_amplitudes.py
@@ -15,7 +15,8 @@
 
 from qiskit.circuit import QuantumCircuit
 from qiskit.extensions.exceptions import ExtensionError
-from .save_data import SaveSingleData, SaveAverageData, default_qubits
+from .save_data import SaveSingleData, SaveAverageData
+from ..default_qubits import default_qubits
 
 
 class SaveAmplitudes(SaveSingleData):

diff --git a/qiskit/providers/aer/library/save_data.py → ...er/library/save_instructions/save_data.py b/qiskit/providers/aer/library/save_data.py → ...er/library/save_instructions/save_data.py
@@ -15,7 +15,6 @@
 
 import copy
 
-from qiskit.circuit import QuantumCircuit, QuantumRegister
 from qiskit.circuit import Instruction
 from qiskit.extensions.exceptions import ExtensionError
 
@@ -143,41 +142,3 @@ def __init__(self,
         if conditional:
             subtype = 'c_' + subtype
         super().__init__(name, num_qubits, label, subtype=subtype, params=params)
-
-
-def default_qubits(circuit, qubits=None):
-    """Helper method to return list of qubits.
-
-    Args:
-        circuit (QuantumCircuit): a quantum circuit.
-        qubits (list or QuantumRegister): Optional, qubits argument,
-            If None the returned list will be all qubits in the circuit.
-            [Default: None]
-
-    Raises:
-            ExtensionError: if default qubits fails.
-
-    Returns:
-        list: qubits list.
-    """
-    # Convert label to string for backwards compatibility
-    # If no qubits are specified we add all qubits so it acts as a barrier
-    # This is needed for full register snapshots like statevector
-    if isinstance(qubits, QuantumRegister):
-        qubits = qubits[:]
-    if not qubits:
-        tuples = []
-        if isinstance(circuit, QuantumCircuit):
-            for register in circuit.qregs:
-                tuples.append(register)
-        if not tuples:
-            raise ExtensionError('no qubits for snapshot')
-        qubits = []
-        for tuple_element in tuples:
-            if isinstance(tuple_element, QuantumRegister):
-                for j in range(tuple_element.size):
-                    qubits.append(tuple_element[j])
-            else:
-                qubits.append(tuple_element)
-
-    return qubits
diff --git a/...viders/aer/library/save_density_matrix.py → .../save_instructions/save_density_matrix.py b/...viders/aer/library/save_density_matrix.py → .../save_instructions/save_density_matrix.py
@@ -14,7 +14,8 @@
 """
 
 from qiskit.circuit import QuantumCircuit
-from .save_data import SaveAverageData, default_qubits
+from .save_data import SaveAverageData
+from ..default_qubits import default_qubits
 
 
 class SaveDensityMatrix(SaveAverageData):

diff --git a/...ers/aer/library/save_expectation_value.py → ...ve_instructions/save_expectation_value.py b/...ers/aer/library/save_expectation_value.py → ...ve_instructions/save_expectation_value.py
diff --git a/.../aer/library/save_matrix_product_state.py → ...instructions/save_matrix_product_state.py b/.../aer/library/save_matrix_product_state.py → ...instructions/save_matrix_product_state.py
@@ -14,7 +14,8 @@
 """
 
 from qiskit.circuit import QuantumCircuit
-from .save_data import SaveSingleData, default_qubits
+from .save_data import SaveSingleData
+from ..default_qubits import default_qubits
 
 
 class SaveMatrixProductState(SaveSingleData):

diff --git a/...oviders/aer/library/save_probabilities.py → ...y/save_instructions/save_probabilities.py b/...oviders/aer/library/save_probabilities.py → ...y/save_instructions/save_probabilities.py
@@ -14,7 +14,8 @@
 """
 
 from qiskit.circuit import QuantumCircuit
-from .save_data import SaveAverageData, default_qubits
+from .save_data import SaveAverageData
+from ..default_qubits import default_qubits
 
 
 class SaveProbabilities(SaveAverageData):

diff --git a/.../providers/aer/library/save_stabilizer.py → ...rary/save_instructions/save_stabilizer.py b/.../providers/aer/library/save_stabilizer.py → ...rary/save_instructions/save_stabilizer.py
@@ -14,7 +14,8 @@
 """
 
 from qiskit.circuit import QuantumCircuit
-from .save_data import SaveSingleData, default_qubits
+from .save_data import SaveSingleData
+from ..default_qubits import default_qubits
 
 
 class SaveStabilizer(SaveSingleData):

diff --git a/qiskit/providers/aer/library/save_state.py → ...r/library/save_instructions/save_state.py b/qiskit/providers/aer/library/save_state.py → ...r/library/save_instructions/save_state.py
@@ -14,7 +14,8 @@
 """
 
 from qiskit.circuit import QuantumCircuit
-from .save_data import SaveSingleData, default_qubits
+from .save_data import SaveSingleData
+from ..default_qubits import default_qubits
 
 
 class SaveState(SaveSingleData):

diff --git a/...providers/aer/library/save_statevector.py → ...ary/save_instructions/save_statevector.py b/...providers/aer/library/save_statevector.py → ...ary/save_instructions/save_statevector.py
@@ -14,7 +14,8 @@
 """
 
 from qiskit.circuit import QuantumCircuit
-from .save_data import SaveSingleData, default_qubits
+from .save_data import SaveSingleData
+from ..default_qubits import default_qubits
 
 
 class SaveStatevector(SaveSingleData):
@@ -23,7 +24,7 @@ def __init__(self, num_qubits,
                  label="statevector",
                  pershot=False,
                  conditional=False):
-        """Create new instruction to save the simualtor statevector.
+        """Create new instruction to save the simulator statevector.
 
         Args:
             num_qubits (int): the number of qubits

diff --git a/qiskit/providers/aer/library/save_unitary.py → ...library/save_instructions/save_unitary.py b/qiskit/providers/aer/library/save_unitary.py → ...library/save_instructions/save_unitary.py
@@ -14,7 +14,8 @@
 """
 
 from qiskit.circuit import QuantumCircuit
-from .save_data import SaveSingleData, default_qubits
+from .save_data import SaveSingleData
+from ..default_qubits import default_qubits
 
 
 class SaveUnitary(SaveSingleData):

diff --git a/qiskit/providers/aer/library/set_instructions/__init__.py b/qiskit/providers/aer/library/set_instructions/__init__.py
@@ -0,0 +1,17 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2018, 2021.
+#
+# 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
+# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
+#
+# 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.
+"""Set state directive instructions for the Aer simulator"""
+
+from .set_statevector import SetStatevector, set_statevector
+from .set_density_matrix import SetDensityMatrix, set_density_matrix
+from .set_unitary import SetUnitary, set_unitary
+from .set_stabilizer import SetStabilizer, set_stabilizer