Removed reset_registers() function from gst.py (to be moved to PEC), …

…updated tests for gst.py

src/qibo/tomography/gate_set_tomography.py

@@ -70,54 +70,6 @@ def measurement_basis(j, circ):
     return new_circ
 
 
-def reset_register(circuit, invert_register):
-    """Returns an inverse circuit of the selected register to prepare the zero state \\(|0\rangle\\).
-        One can then add inverse_circuit to the original circuit by addition:
-            circ_with_inverse = circ.copy()
-            circ_with_inverse.add(inverse_circuit.on_qubits(invert_register))
-        where register_to_reset = 0, 1, or [0,1].
-
-        Args:
-        circuit (:class:`qibo.models.Circuit`): original circuit
-        invert_register (string): Qubit(s) to reset:
-            'sp_0' (qubit 0);
-            'sp_1' (qubit 1); or
-            'sp_t' (both qubits)
-            where 'sp' is an abbreviation for state_preparation.
-    Returns:
-        inverse_circuit (:class:`qibo.models.Circuit`): Inverse of the input circuit's register.
-    """
-
-    if invert_register == "sp_0" or invert_register == "sp_1":
-        if invert_register == "sp_0":
-            register_to_reset = 0
-        elif invert_register == "sp_1":
-            register_to_reset = 1
-
-        new_circ = Circuit(1)
-        for data in circuit.raw["queue"]:
-            init_kwargs = data.get("init_kwargs", {})
-            if data["_target_qubits"][0] == register_to_reset:
-                new_circ.add(getattr(gates, data["_class"])(0, **init_kwargs))
-
-    elif invert_register == "sp_t":
-        new_circ = circuit.copy()
-
-    else:
-        raise_error(
-            NameError,
-            f"{invert_register} not recognized. Input "
-            "sp_0"
-            " to reset qubit 0, "
-            "sp_1"
-            " to reset qubit 1, or "
-            "sp_t"
-            " to reset both qubits.",
-        )
-
-    return new_circ.invert()
-
-
 def GST_execute_circuit(circuit, k, j, nshots=int(1e4), backend=None):
     """Executes a circuit used in gate set tomography and processes the
         measurement outcomes for the Pauli Transfer Matrix notation. The circuit

tests/test_tomography_gate_set_tomography.py

@@ -9,7 +9,6 @@
     execute_GST,
     measurement_basis,
     prepare_states,
-    reset_register,
 )
 
 
@@ -152,119 +151,6 @@ def test_measurement_basis_invalid_j_valid_nqubits(j, nqubits):
         new_circuit = measurement_basis(j, test_circuit)
 
 
-def test_reset_register_valid_string_1qb():
-    # Test for valid string
-    nqubits = 1
-    test_circuit = qibo.models.Circuit(nqubits)
-    test_circuit.add(gates.H(0))
-
-    invert_register = "sp_0"
-    inverse_circuit = reset_register(test_circuit, invert_register)
-
-    correct_gates = [
-        [gates.H(0)],
-    ]
-    for groundtruth, gate in zip(correct_gates, inverse_circuit.queue):
-        assert isinstance(gate, type(groundtruth[0]))
-
-
-def test_reset_register_sp_0_twoqubitcircuit():
-    # Test resetting qubit 0
-    nqubits = 2
-    test_circuit = qibo.models.Circuit(nqubits)
-    test_circuit.add(gates.H(0))
-    test_circuit.add(gates.S(1))
-
-    inverse_circuit = reset_register(test_circuit, "sp_0")
-
-    correct_gates = [
-        [gates.H(0)],
-    ]
-
-    for groundtruth, gate in zip(correct_gates, inverse_circuit.queue):
-        assert isinstance(gate, type(groundtruth[0]))
-
-
-def test_reset_register_sp_0_singlequbitcircuit():
-    # Test resetting qubit 0
-
-    nqubits = 1
-    test_circuit = qibo.models.Circuit(nqubits)
-    test_circuit.add(gates.H(0))
-    test_circuit.add(gates.RX(0, np.pi / 3))
-
-    inverse_circuit = reset_register(test_circuit, "sp_0")
-
-    correct_gates = [
-        [gates.RX(0, np.pi / 3).dagger()],
-        [gates.H(0)],
-    ]
-
-    for groundtruth, gate in zip(correct_gates, inverse_circuit.queue):
-        assert isinstance(gate, type(groundtruth[0]))
-
-
-def test_reset_register_sp_1_twoqubitcircuit():
-    # Test resetting qubit 1
-    nqubits = 2
-    test_circuit = qibo.models.Circuit(nqubits)
-    test_circuit.add(gates.H(0))
-    test_circuit.add(gates.S(1))
-
-    inverse_circuit = reset_register(test_circuit, "sp_1")
-
-    correct_gates = [[gates.S(0).dagger()]]
-
-    for groundtruth, gate in zip(correct_gates, inverse_circuit.queue):
-        assert isinstance(gate, type(groundtruth[0]))
-
-
-def test_reset_register_sp_1_singlequbitcircuit():
-    # Test resetting qubit 1
-    nqubits = 2
-    test_circuit = qibo.models.Circuit(nqubits)
-    test_circuit.add(gates.H(0))
-    test_circuit.add(gates.S(0))
-    test_circuit.add(gates.RX(1, np.pi / 3))
-
-    inverse_circuit = reset_register(test_circuit, "sp_1")
-
-    correct_gates = [[gates.RX(1, np.pi / 3).dagger()]]
-
-    for groundtruth, gate in zip(correct_gates, inverse_circuit.queue):
-        assert isinstance(gate, type(groundtruth[0]))
-
-
-def test_reset_register_sp_t():
-    # Test resetting both qubits
-    nqubits = 2
-    test_circuit = qibo.models.Circuit(nqubits)
-    test_circuit.add(gates.H(0))
-    test_circuit.add(gates.CNOT(0, 1))
-
-    inverse_circuit = reset_register(test_circuit, "sp_t")
-
-    correct_gates = [
-        [gates.CNOT(0, 1)],
-        [gates.H(0)],
-    ]
-    for groundtruth, gate in zip(correct_gates, inverse_circuit.queue):
-        assert isinstance(gate, type(groundtruth[0]))
-
-
-def test_reset_register_invalid_string():
-    # Test resetting both qubits
-
-    nqubits = 2
-    test_circuit = qibo.models.Circuit(nqubits)
-    test_circuit.add(gates.H(0))
-    test_circuit.add(gates.CNOT(0, 1))
-
-    # Check if NameError is raised
-    with pytest.raises(NameError):
-        inverse_circuit = reset_register(test_circuit, "sp_2")
-
-
 def test_GST_execute_circuit_1qb_j0():
     np.random.seed(42)
     nqubits = 1
@@ -391,94 +277,6 @@ def test_GST_two_qubit_with_CRXgate(backend):
     backend.assert_allclose(test_result, control_result, rtol=5e-2, atol=5e-2)
 
 
-def test_GST_one_qubit_with_gate_with_valid_reset_register_string(backend):
-    nqubits = 1
-    invert_register = "sp_0"
-    control_result = execute_GST(
-        nqubits=nqubits, gate=None, invert_register=invert_register
-    )
-    test_result = execute_GST(
-        nqubits=nqubits, gate=None, invert_register=invert_register
-    )
-    backend.assert_allclose(test_result, control_result, rtol=5e-2, atol=5e-2)
-
-
-def test_GST_two_qubit_with_gate_with_valid_reset_register_string(backend):
-    nqubits = 2
-    invert_register = "sp_1"
-    np.random.seed(42)
-    control_result = execute_GST(
-        nqubits=nqubits, gate=None, invert_register=invert_register, backend=backend
-    )
-    np.random.seed(42)
-    test_result = execute_GST(
-        nqubits=nqubits, gate=None, invert_register=invert_register, backend=backend
-    )
-
-    backend.assert_allclose(test_result, control_result, rtol=5e-2, atol=5e-2)
-
-
-def test_GST_one_qubit_with_param_gate_with_valid_reset_register_string(backend):
-    nqubits = 1
-    test_gate = gates.RX(0, np.pi / 7)
-    invert_register = "sp_0"
-    control_result = execute_GST(
-        nqubits=nqubits, gate=None, invert_register=invert_register
-    )
-    test_result = execute_GST(
-        nqubits=nqubits, gate=None, invert_register=invert_register
-    )
-    backend.assert_allclose(test_result, control_result, rtol=5e-2, atol=5e-2)
-
-
-def test_GST_two_qubit_with_param_gate_with_valid_reset_register_string(backend):
-    nqubits = 2
-    test_gate = gates.CNOT(0, 1)
-    invert_register = "sp_1"
-    np.random.seed(42)
-    control_result = execute_GST(
-        nqubits=nqubits, gate=None, invert_register=invert_register, backend=backend
-    )
-    np.random.seed(42)
-    test_result = execute_GST(
-        nqubits=nqubits, gate=None, invert_register=invert_register, backend=backend
-    )
-
-    backend.assert_allclose(test_result, control_result, rtol=5e-2, atol=5e-2)
-
-
-def test_GST_two_qubit_with_gate_with_valid_reset_register_string(backend):
-    nqubits = 2
-    test_gate = gates.CZ(0, 1)
-    invert_register = "sp_t"
-    np.random.seed(42)
-    control_result = execute_GST(
-        nqubits=nqubits,
-        gate=test_gate,
-        invert_register=invert_register,
-        backend=backend,
-    )
-    np.random.seed(42)
-    test_result = execute_GST(
-        nqubits=nqubits,
-        gate=test_gate,
-        invert_register=invert_register,
-        backend=backend,
-    )
-
-    backend.assert_allclose(test_result, control_result, rtol=5e-2, atol=5e-2)
-
-
-def test_GST_two_qubit_with_gate_with_invalid_reset_register_string():
-    nqubits = 2
-    test_gate = gates.CZ(0, 1)
-    invert_register = "sp_3"
-    with pytest.raises(NameError):
-        result = execute_GST(
-            nqubits=nqubits, gate=test_gate, invert_register=invert_register
-        )
-
-
 def test_GST_empty_circuit_with_invalid_qb(backend):
     nqubits = 3
     # Check if ValueError is raised