Fix a bug in LEAP and add tests for LEAP stateprep

qsearch/leap_compiler.py

@@ -146,7 +146,8 @@ def compile(self, options=Options()):
             logger.logprint("This gateset has no branching factor so only an initial optimization will be run.")
             root = initial_layer
             result = options.solver.solve_for_unitary(options.backend.prepare_circuit(root, options), options)
-            return (root, result[1])
+            value = options.eval_func(U, result[0])
+            return ((root, result[1]), value, 0)
 
         parallel = options.parallelizer(options)
         # TODO move these print statements somewhere else

tests/test_stateprep.py

@@ -20,24 +20,25 @@ def simulate_statevector(qc):
     return np.array(result.get_statevector(qc))
 
 
-
-def qsearch_stateprep(project, target_state):
+def qsearch_stateprep(project, target_state, leap=False):
     stateprep_options = qsearch.Options(target_state=target_state,smart_defaults=qsearch.defaults.stateprep_smart_defaults)
     project.add_compilation("stateprep",stateprep_options.target,options=stateprep_options)
+    if leap:
+        project['compiler_class'] = leap_compiler.LeapCompiler
     project.run()
     qiskit_code = project.assemble("stateprep", assembler=qsearch.assemblers.ASSEMBLER_QISKIT)
     locals = {}
     exec(qiskit_code, globals(), locals)
     return locals['qc']
 
-STATES = map(np.array, (
+STATES = list(map(np.array, (
     [1/np.sqrt(2),-1/np.sqrt(2)],
     [0.5,0.5,0.5,0,0,0,0,0.5],
     [0,0.5,0.5j,0,-0.5,0,0,0,-0.5j,0,0,0,0,0,0,0]
-))
+)))
 
 @pytest.mark.skipif(qiskit is None, reason="Qiskit is not installed")
-@pytest.mark.parametrize("target_state", STATES, ids=lambda state: repr(state[:5]))
+@pytest.mark.parametrize("target_state", STATES, ids=lambda state: repr(state))
 def test_stateprep_roundtrip(project, target_state):
     qc = qsearch_stateprep(project, utils.endian_reverse(target_state))
     output_state = simulate_statevector(qc)
@@ -48,3 +49,17 @@ def test_stateprep_roundtrip(project, target_state):
         qc2.id(i)
     output_state_ibm = simulate_statevector(qc2)
     assert np.isclose(np.abs(np.vdot(output_state,output_state_ibm)),1)
+
+
+@pytest.mark.skipif(qiskit is None, reason="Qiskit is not installed")
+@pytest.mark.parametrize("target_state", STATES, ids=lambda state: repr(state))
+def test_stateprep_leap_roundtrip(project, target_state):
+    qc = qsearch_stateprep(project, utils.endian_reverse(target_state), leap=True)
+    output_state = simulate_statevector(qc)
+    num_qubits = int(np.log2(target_state.shape[0]))
+    qc2 = QuantumCircuit(num_qubits)
+    qc2.initialize(target_state, list(range(num_qubits)))
+    for i in range(num_qubits):
+        qc2.id(i)
+    output_state_ibm = simulate_statevector(qc2)
+    assert np.isclose(np.abs(np.vdot(output_state,output_state_ibm)),1)