Support Parametric Circuits

qiskit_braket_provider/providers/adapter.py

@@ -2,7 +2,13 @@
 from typing import Callable, Dict, Iterable, List, Optional, Tuple, Union
 
 from braket.aws import AwsDevice
-from braket.circuits import Circuit, Instruction, gates, result_types
+from braket.circuits import (
+    Circuit,
+    FreeParameter,
+    Instruction,
+    gates,
+    result_types,
+)
 from braket.device_schema import (
     DeviceActionType,
     GateModelQpuParadigmProperties,
@@ -44,6 +50,7 @@
     SXGate,
     TdgGate,
     TGate,
+    UGate,
     U1Gate,
     U2Gate,
     U3Gate,
@@ -56,6 +63,7 @@
 from qiskit_braket_provider.exception import QiskitBraketException
 
 qiskit_to_braket_gate_names_mapping = {
+    "u": "u",
     "u1": "u1",
     "u2": "u2",
     "u3": "u3",
@@ -89,6 +97,13 @@
 
 
 qiskit_gate_names_to_braket_gates: Dict[str, Callable] = {
+    "u": lambda theta, phi, lam: [
+        gates.Rz(lam),
+        gates.Rx(pi / 2),
+        gates.Rz(theta),
+        gates.Rx(-pi / 2),
+        gates.Rz(phi),
+    ],
     "u1": lambda lam: [gates.Rz(lam)],
     "u2": lambda phi, lam: [gates.Rz(lam), gates.Ry(pi / 2), gates.Rz(phi)],
     "u3": lambda theta, phi, lam: [
@@ -128,6 +143,7 @@
 
 
 qiskit_gate_name_to_braket_gate_mapping: Dict[str, Optional[QiskitInstruction]] = {
+    "u": UGate(Parameter("theta"), Parameter("phi"), Parameter("lam")),
     "u1": U1Gate(Parameter("theta")),
     "u2": U2Gate(Parameter("theta"), Parameter("lam")),
     "u3": U3Gate(Parameter("theta"), Parameter("phi"), Parameter("lam")),
@@ -362,6 +378,10 @@ def convert_qiskit_to_braket_circuit(circuit: QuantumCircuit) -> Circuit:
             if hasattr(qiskit_gates[0], "params"):
                 params = qiskit_gates[0].params
 
+            for i, param in enumerate(params):
+                if isinstance(param, Parameter):
+                    params[i] = FreeParameter(param.name)
+
             for gate in qiskit_gate_names_to_braket_gates[name](*params):
                 instruction = Instruction(
                     # Getting the index from the bit mapping

tests/providers/test_adapter.py

@@ -1,9 +1,13 @@
 """Tests for Qiskti to Braket adapter."""
 from unittest import TestCase
 
-from braket.circuits import Circuit
+from braket.circuits import Circuit, FreeParameter
+import numpy as np
+from qiskit import QuantumCircuit
+from qiskit.circuit import Parameter
 
 from qiskit_braket_provider.providers.adapter import (
+    convert_qiskit_to_braket_circuit,
     qiskit_gate_name_to_braket_gate_mapping,
     qiskit_gate_names_to_braket_gates,
     qiskit_to_braket_gate_names_mapping,
@@ -26,6 +30,35 @@ def test_mappers(self):
             list(sorted(qiskit_gate_name_to_braket_gate_mapping.keys())),
         )
 
+    def test_convert_parametric_qiskit_to_braket_circuit(self):
+        """Tests convert_qiskit_to_braket_circuit works with parametric circuits."""
+
+        theta = Parameter("θ")
+        phi = Parameter("φ")
+        lam = Parameter("λ")
+        qiskit_circuit = QuantumCircuit(1, 1)
+        qiskit_circuit.rz(theta, 0)
+        qiskit_circuit.u(theta, phi, lam, 0)
+        qiskit_circuit.u(theta, phi, np.pi, 0)
+        braket_circuit = convert_qiskit_to_braket_circuit(qiskit_circuit)
+
+        braket_circuit_ans = (
+            Circuit()  # pylint: disable=no-member
+            .rz(0, FreeParameter("θ"))
+            .rz(0, FreeParameter("λ"))
+            .rx(0, np.pi / 2)
+            .rz(0, FreeParameter("θ"))
+            .rx(0, -np.pi / 2)
+            .rz(0, FreeParameter("φ"))
+            .rz(0, np.pi)
+            .rx(0, np.pi / 2)
+            .rz(0, FreeParameter("θ"))
+            .rx(0, -np.pi / 2)
+            .rz(0, FreeParameter("φ"))
+        )
+
+        self.assertEqual(braket_circuit, braket_circuit_ans)
+
 
 class TestVerbatimBoxWrapper(TestCase):
     """Test wrapping in Verbatim box."""