1qb unitary gates

unitaryfund · Apr 23, 2022 · 146833c · 146833c
1 parent 2b4c09a
commit 146833c
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Showing 2 changed files with 35 additions and 18 deletions.
diff --git a/pennylane_qrack/qrack_device.py b/pennylane_qrack/qrack_device.py
@@ -121,9 +121,11 @@ def apply_operations(self, operations):
             elif isinstance(op, BasisState):
                 self._apply_basis_state(op)
             elif isinstance(op, QubitUnitary):
-                raise DeviceError(
-                    "Operation {} is not supported on a {} device.".format(op.name, self.short_name)
-                )
+                if len(op.wires) > 1:
+                    raise DeviceError(
+                        "Operation {} is not supported on a {} device, except for single wires.".format(op.name, self.short_name)
+                    )
+                self._apply_qubit_unitary(op)
             else:
                 self._apply_gate(op)
 
@@ -235,6 +237,21 @@ def _apply_gate(self, op):
                 "Operation {} is not supported on a {} device.".format(op.name, self.short_name)
             )
 
+    def _apply_qubit_unitary(self, op):
+        """Apply unitary to state"""
+        # translate op wire labels to consecutive wire labels used by the device
+        device_wires = self.map_wires(op.wires)
+        par = op.parameters
+
+        if len(par[0]) != 2 ** len(device_wires):
+            raise ValueError("Unitary matrix must be of shape (2**wires, 2**wires).")
+
+        if op.inverse:
+            par[0] = par[0].conj().T
+
+        matrix = par[0].flatten().tolist()
+        self._state.mtrx(matrix, device_wires.labels[0])
+
     def analytic_probability(self, wires=None):
         """Return the (marginal) analytic probability of each computational basis state."""
         if self._state is None:

diff --git a/tests/test_apply.py b/tests/test_apply.py
@@ -243,21 +243,21 @@ def test_two_qubit_no_parameters(self, init_state, op, mat, tol):
         expected = mat @ state
         assert np.allclose(res, expected, tol)
 
-    # @pytest.mark.parametrize("mat", [U, U2])
-    # def test_qubit_unitary(self, init_state, mat, tol):
-    #     """Test QubitUnitary application"""
-    #
-    #     N = int(np.log2(len(mat)))
-    #     dev = QrackDevice(N)
-    #     state = init_state(N)
-    #
-    #     op = qml.QubitUnitary(mat, wires=list(range(N)))
-    #     dev.apply([qml.QubitStateVector(state, wires=list(range(N))), op])
-    #     dev._obs_queue = []
-    #
-    #     res = dev.state
-    #     expected = mat @ state
-    #     assert np.allclose(res, expected, tol)
+    @pytest.mark.parametrize("mat", [U])
+    def test_qubit_unitary(self, init_state, mat, tol):
+        """Test QubitUnitary application"""
+
+        N = int(np.log2(len(mat)))
+        dev = QrackDevice(N)
+        state = init_state(N)
+
+        op = qml.QubitUnitary(mat, wires=list(range(N)))
+        dev.apply([qml.QubitStateVector(state, wires=list(range(N))), op])
+        dev._obs_queue = []
+
+        res = dev.state
+        expected = mat @ state
+        assert np.allclose(res, expected, tol)
 
     def test_invalid_qubit_state_unitary(self):
         """Test that an exception is raised if the