From a63cc4d7c0bae530e3bfdd4de78f41b62ddff307 Mon Sep 17 00:00:00 2001 From: Matthew Date: Fri, 9 Aug 2024 15:11:06 +0800 Subject: [PATCH] Updated docstrings for get_noisy_circuits and ZNE --- src/qibo/models/error_mitigation.py | 30 +++++++++++++---------------- 1 file changed, 13 insertions(+), 17 deletions(-) diff --git a/src/qibo/models/error_mitigation.py b/src/qibo/models/error_mitigation.py index f9fa712763..94cd05c6be 100644 --- a/src/qibo/models/error_mitigation.py +++ b/src/qibo/models/error_mitigation.py @@ -59,11 +59,10 @@ def get_noisy_circuit( Args: circuit (:class:`qibo.models.circuit.Circuit`): circuit to modify. num_insertions (int): number of insertion gate pairs / global unitary folds to add. - global_unitary_folding (bool): Default True. Global unitary folding is carried out by default. - Global unitary folding takes precedence over insertion_gate. - insertion_gate (str, optional): gate to be used in the insertion. - If ``"RX"``, the gate used is :math:``RX(\\pi / 2)``. - Otherwise, the other gate is ``"CNOT"``. + global_unitary_folding (bool): If ``True``, noise is increased by global unitary folding. + If ``False``, local unitary folding is used. Defaults to ``True``. + insertion_gate (str, optional): gate to be folded in the local unitary folding. + If ``RX``, the gate used is :math:``RX(\\pi / 2)``. Otherwise, it is the ``CNOT`` gate. Returns: :class:`qibo.models.Circuit`: circuit with the inserted gate pairs or with global folding. @@ -71,26 +70,22 @@ def get_noisy_circuit( from qibo import Circuit # pylint: disable=import-outside-toplevel - if global_unitary_folding: # pragma: no cover + if global_unitary_folding: - # Create a copy of input circuit without measurements copy_c = Circuit(**circuit.init_kwargs) for g in circuit.queue: if not isinstance(g, gates.M): copy_c.add(g) - # Initialize noisy circuit noisy_circuit = copy_c - # Add (U^+ U)s for _ in range(num_insertions): noisy_circuit += copy_c.invert() + copy_c - # Add measurements according to the original circuit for m in circuit.measurements: noisy_circuit.add(m) - else: # pragma: no cover + else: if insertion_gate is None or insertion_gate not in ( "CNOT", "RX", @@ -109,7 +104,7 @@ def get_noisy_circuit( i_gate = gates.CNOT if insertion_gate == "CNOT" else gates.RX theta = np.pi / 2 - noisy_circuit = circuit.__class__(**circuit.init_kwargs) + noisy_circuit = Circuit(**circuit.init_kwargs) for gate in circuit.queue: noisy_circuit.add(gate) @@ -121,9 +116,9 @@ def get_noisy_circuit( for _ in range(num_insertions): noisy_circuit.add(gates.CNOT(control, target)) noisy_circuit.add(gates.CNOT(control, target)) - # elif gate.init_kwargs["theta"] == theta: elif insertion_gate == "RX": qubit = gate.qubits[0] + theta = gate.init_kwargs["theta"] for _ in range(num_insertions): noisy_circuit.add(gates.RX(qubit, theta=theta)) noisy_circuit.add(gates.RX(qubit, theta=-theta)) @@ -160,9 +155,10 @@ def ZNE( nshots (int, optional): Number of shots. Defaults to :math:`10000`. solve_for_gammas (bool, optional): If ``True``, explicitly solve the equations to obtain the ``gamma`` coefficients. Default is ``False``. - insertion_gate (str, optional): gate to be used in the insertion. - If ``"RX"``, the gate used is :math:``RX(\\pi / 2)``. - Defaults to ``"CNOT"``. + global_unitary_folding (bool, optional): If ``True``, noise is increased by global unitary folding. + If ``False``, local unitary folding is used. Defaults to ``True``. + insertion_gate (str, optional): gate to be folded in the local unitary folding. + If ``RX``, the gate used is :math:``RX(\\pi / 2)``. Otherwise, it is the ``CNOT`` gate. readout (dict, optional): a dictionary that may contain the following keys: * ncircuits: int, specifies the number of random circuits to use for the randomized method of readout error mitigation. @@ -212,7 +208,7 @@ def ZNE( gamma = get_gammas(noise_levels, analytical=solve_for_gammas) - return np.sum(gamma * expected_values) + return expected_values, gamma, np.sum(gamma * expected_values) def sample_training_circuit_cdr(