Add tests and release notes

releasenotes/notes/set-state-a029d86b357df0dd.yaml

@@ -0,0 +1,19 @@
+---
+features:
+  - |
+    Adds instructions for setting the state of the simulators. These
+    instructions must be defined on the full number of qubits in the circuit.
+    They can be applied at any point in a circuit and will override the
+    simulator state with the one specified. Added instructions are
+
+    * :class:`qiskit.providers.aer.library.SetStatevector`
+    * :class:`qiskit.providers.aer.library.SetDensityMatrix`
+    * :class:`qiskit.providers.aer.library.SetStabilizer`
+    * :class:`qiskit.providers.aer.library.SetUnitary`
+    
+    These instruction can also be appended to a quantum circuit by using the
+    :class:`~qiskit.providers.aer.library.set_statevector`,
+    :class:`~qiskit.providers.aer.library.set_density_matrix`,
+    :class:`~qiskit.providers.aer.library.set_stabilizer`,
+    :class:`~qiskit.providers.aer.library.set_unitary`
+    circuit methods which are added to ``QuantumCircuit`` when importing Aer.

test/terra/backends/qasm_simulator/qasm_set_state.py

@@ -0,0 +1,122 @@
+# 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.
+"""
+QasmSimulator Integration Tests for set state instructions
+"""
+
+from ddt import ddt, data
+import qiskit.quantum_info as qi
+from qiskit import QuantumCircuit, assemble
+from qiskit.providers.aer import QasmSimulator
+
+
+@ddt
+class QasmSetStateTests:
+    """QasmSimulator set state instruction tests."""
+
+    SIMULATOR = QasmSimulator()
+    BACKEND_OPTS = {}
+
+    @data(1, 2, 3, 4, 5)
+    def test_set_statevector(self, num_qubits):
+        """Test SetStatevector for instruction"""
+
+        SUPPORTED_METHODS = [
+            'automatic', 'statevector', 'statevector_gpu',
+            'statevector_thrust'
+        ]
+
+        seed = 100
+        save_label = 'state'
+
+        target = qi.random_statevector(2 ** num_qubits, seed=seed)
+
+        circ = QuantumCircuit(num_qubits)
+        circ.set_statevector(target)
+        circ.save_statevector(label=save_label)
+
+        # Run
+        opts = self.BACKEND_OPTS.copy()
+        qobj = assemble(circ, self.SIMULATOR)
+        result = self.SIMULATOR.run(qobj, **opts).result()
+        method = opts.get('method', 'automatic')
+        if method not in SUPPORTED_METHODS:
+            self.assertFalse(result.success)
+        else:
+            self.assertTrue(result.success)
+            data = result.data(0)
+            self.assertIn(save_label, data)
+            value = qi.Statevector(result.data(0)[save_label])
+            self.assertAlmostEqual(value, target)
+
+    @data(1, 2, 3)
+    def test_set_density_matrix(self, num_qubits):
+        """Test SetDensityMatrix instruction"""
+
+        SUPPORTED_METHODS = [
+            'automatic', 'density_matrix', 'density_matrix_gpu',
+            'density_matrix_thrust'
+        ]
+
+        seed = 100
+        save_label = 'state'
+
+        target = qi.random_density_matrix(2 ** num_qubits, seed=seed)
+
+        circ = QuantumCircuit(num_qubits)
+        circ.set_density_matrix(target)
+        circ.save_density_matrix(label=save_label)
+
+        # Run
+        opts = self.BACKEND_OPTS.copy()
+        qobj = assemble(circ, self.SIMULATOR)
+        result = self.SIMULATOR.run(qobj, **opts).result()
+        method = opts.get('method', 'automatic')
+        if method not in SUPPORTED_METHODS:
+            self.assertFalse(result.success)
+        else:
+            self.assertTrue(result.success)
+            data = result.data(0)
+            self.assertIn(save_label, data)
+            value = qi.DensityMatrix(result.data(0)[save_label])
+            self.assertAlmostEqual(value, target)
+
+    @data(1, 2, 3)
+    def test_set_stabilizer(self, num_qubits):
+        """Test SetStabilizer instruction"""
+
+        SUPPORTED_METHODS = [
+            'automatic', 'stabilizer'
+        ]
+
+        seed = 100
+        save_label = 'state'
+
+        target = qi.random_clifford(num_qubits, seed=seed)
+
+        circ = QuantumCircuit(num_qubits)
+        circ.set_stabilizer(target)
+        circ.save_stabilizer(label=save_label)
+
+        # Run
+        opts = self.BACKEND_OPTS.copy()
+        qobj = assemble(circ, self.SIMULATOR)
+        result = self.SIMULATOR.run(qobj, **opts).result()
+        method = opts.get('method', 'automatic')
+        if method not in SUPPORTED_METHODS:
+            self.assertFalse(result.success)
+        else:
+            self.assertTrue(result.success)
+            data = result.data(0)
+            self.assertIn(save_label, data)
+            value = qi.Clifford.from_dict(result.data(0)[save_label])
+            self.assertEqual(value, target)

test/terra/backends/test_qasm_simulator.py

@@ -44,6 +44,7 @@
 from test.terra.backends.qasm_simulator.qasm_noise import QasmKrausNoiseTests
 # Save data tests
 from test.terra.backends.qasm_simulator.qasm_save import QasmSaveDataTests
+from test.terra.backends.qasm_simulator.qasm_set_state import QasmSetStateTests
 # Snapshot tests
 from test.terra.backends.qasm_simulator.qasm_snapshot import QasmSnapshotStatevectorTests
 from test.terra.backends.qasm_simulator.qasm_snapshot import QasmSnapshotDensityMatrixTests
@@ -86,6 +87,7 @@ class TestQasmSimulator(common.QiskitAerTestCase,
                         QasmKrausNoiseTests,
                         QasmBasicsTests,
                         QasmSaveDataTests,
+                        QasmSetStateTests,
                         QasmStandardGateStatevectorTests,
                         QasmStandardGateDensityMatrixTests,
                         QasmDelayGateTests,

test/terra/backends/test_qasm_simulator_density_matrix.py

@@ -46,6 +46,7 @@
 from test.terra.backends.qasm_simulator.qasm_fusion import QasmFusionTests
 # Save data tests
 from test.terra.backends.qasm_simulator.qasm_save import QasmSaveDataTests
+from test.terra.backends.qasm_simulator.qasm_set_state import QasmSetStateTests
 # Snapshot tests
 from test.terra.backends.qasm_simulator.qasm_snapshot import QasmSnapshotStatevectorTests
 from test.terra.backends.qasm_simulator.qasm_snapshot import QasmSnapshotDensityMatrixTests
@@ -63,7 +64,7 @@ class DensityMatrixTests(
         QasmAlgorithmTests, QasmAlgorithmTestsWaltzBasis,
         QasmAlgorithmTestsMinimalBasis, QasmUnitaryGateTests, QasmDiagonalGateTests,
         QasmReadoutNoiseTests, QasmPauliNoiseTests, QasmResetNoiseTests,
-        QasmKrausNoiseTests, QasmSaveDataTests,
+        QasmKrausNoiseTests, QasmSaveDataTests, QasmSetStateTests,
         QasmSnapshotStatevectorTests,
         QasmSnapshotDensityMatrixTests, QasmSnapshotProbabilitiesTests,
         QasmSnapshotExpValPauliTests, QasmSnapshotExpValPauliNCTests,

test/terra/backends/test_qasm_simulator_stabilizer.py

@@ -34,6 +34,7 @@
 from test.terra.backends.qasm_simulator.qasm_noise import QasmResetNoiseTests
 # Save data tests
 from test.terra.backends.qasm_simulator.qasm_save import QasmSaveDataTests
+from test.terra.backends.qasm_simulator.qasm_set_state import QasmSetStateTests
 # Snapshot tests
 from test.terra.backends.qasm_simulator.qasm_snapshot import QasmSnapshotStatevectorTests
 from test.terra.backends.qasm_simulator.qasm_snapshot import QasmSnapshotDensityMatrixTests
@@ -56,6 +57,7 @@ class TestQasmStabilizerSimulator(common.QiskitAerTestCase,
                                   QasmResetNoiseTests,
                                   QasmPauliNoiseTests,
                                   QasmSaveDataTests,
+                                  QasmSetStateTests,
                                   QasmSnapshotStatevectorTests,
                                   QasmSnapshotDensityMatrixTests,
                                   QasmSnapshotProbabilitiesTests,

test/terra/backends/test_qasm_simulator_statevector.py

@@ -45,6 +45,7 @@
 from test.terra.backends.qasm_simulator.qasm_noise import QasmKrausNoiseTests
 # Save data tests
 from test.terra.backends.qasm_simulator.qasm_save import QasmSaveDataTests
+from test.terra.backends.qasm_simulator.qasm_set_state import QasmSetStateTests
 # Snapshot tests
 from test.terra.backends.qasm_simulator.qasm_snapshot import QasmSnapshotStatevectorTests
 from test.terra.backends.qasm_simulator.qasm_snapshot import QasmSnapshotDensityMatrixTests
@@ -71,7 +72,7 @@ class StatevectorTests(
         QasmReadoutNoiseTests, QasmPauliNoiseTests, QasmThreadManagementTests,
         QasmFusionTests, QasmDelayMeasureTests, QasmQubitsTruncateTests,
         QasmResetNoiseTests, QasmKrausNoiseTests, QasmBasicsTests,
-        QasmSaveDataTests,
+        QasmSaveDataTests, QasmSetStateTests,
         QasmSnapshotStatevectorTests, QasmSnapshotDensityMatrixTests,
         QasmSnapshotProbabilitiesTests, QasmSnapshotExpValPauliTests,
         QasmSnapshotExpValPauliNCTests, QasmSnapshotExpValMatrixTests,