Merge pull request #1090 from qiboteam/clifford_label

Fix ``Clifford`` label on controlled gates

src/qibo/gates/gates.py

@@ -1040,7 +1040,6 @@ def __init__(self, q0, q1):
         self.control_qubits = (q0,)
         self.target_qubits = (q1,)
         self.init_args = [q0, q1]
-        self.clifford = True
         self.unitary = True
 
     @property
@@ -1082,7 +1081,6 @@ def __init__(self, q0, q1):
         self.control_qubits = (q0,)
         self.target_qubits = (q1,)
         self.init_args = [q0, q1]
-        self.clifford = True
         self.unitary = True
 
     @property
@@ -1119,7 +1117,7 @@ def __init__(self, q0, q1, theta, trainable=True):
         self.parameters = theta
         self.unitary = True
 
-        if isinstance(theta, (float, int)) and (theta % (np.pi / 2)).is_integer():
+        if isinstance(theta, (float, int)) and (theta % np.pi).is_integer():
             self.clifford = True
 
         self.init_args = [q0, q1]
@@ -2086,7 +2084,6 @@ def __init__(self, q0, q1, q2):
         self.control_qubits = (q0, q1)
         self.target_qubits = (q2,)
         self.init_args = [q0, q1, q2]
-        self.clifford = True
         self.unitary = True
 
     @property

tests/test_gates_gates.py

@@ -554,7 +554,7 @@ def test_csx(backend):
     backend.assert_allclose(final_state_decompose, target_state)
 
     assert gates.CSX(0, 1).qasm_label == "csx"
-    assert gates.CSX(0, 1).clifford
+    assert not gates.CSX(0, 1).clifford
     assert gates.CSX(0, 1).unitary
 
 
@@ -590,7 +590,7 @@ def test_csxdg(backend):
     backend.assert_allclose(final_state_decompose, target_state)
 
     assert gates.CSXDG(0, 1).qasm_label == "csxdg"
-    assert gates.CSXDG(0, 1).clifford
+    assert not gates.CSXDG(0, 1).clifford
     assert gates.CSXDG(0, 1).unitary
 
 
@@ -624,7 +624,7 @@ def test_cun(backend, name, params):
 
     if name in ["CRX", "CRY", "CRZ"]:
         theta = params["theta"]
-        if (theta % (np.pi / 2)).is_integer():
+        if (theta % np.pi).is_integer():
             assert gate.clifford
         else:
             assert not gate.clifford
@@ -1098,7 +1098,7 @@ def test_toffoli(backend, applyx):
     backend.assert_allclose(final_state, target_state)
 
     assert gatelist[-1].qasm_label == "ccx"
-    assert gates.TOFFOLI(0, 1, 2).clifford
+    assert not gates.TOFFOLI(0, 1, 2).clifford
     assert gates.TOFFOLI(0, 1, 2).unitary