Source code for pytket.utils.measurements

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from typing import Iterable
from pytket.circuit import Circuit, Bit
from pytket.pauli import Pauli, QubitPauliString
from .operators import QubitPauliOperator


[docs] def append_pauli_measurement(pauli_string: QubitPauliString, circ: Circuit) -> None: """Appends measurement instructions to a given circuit, measuring each qubit in a given basis. :param pauli_string: The pauli string to measure :type pauli_string: QubitPauliString :param circ: Circuit to add measurement to. :type circ: Circuit """ measured_qbs = [] for qb, p in pauli_string.map.items(): if p == Pauli.I: continue measured_qbs.append(qb) if p == Pauli.X: circ.H(qb) elif p == Pauli.Y: circ.Rx(0.5, qb) for b_idx, qb in enumerate(measured_qbs): unit = Bit(b_idx) circ.add_bit(unit, False) circ.Measure(qb, unit)
def _all_pauli_measurements( operator: QubitPauliOperator, circ: Circuit ) -> Iterable[Circuit]: """For each term in the operator, yields a copy of the given circuit with the appropriate measurements on each qubit. The trivial term is omitted. :param operator: The operator :type operator: QubitPauliOperator :param circ: The circuit generating the desired state :type circ: Circuit :return: List of circuits in order of term from the operator :rtype: Iterable[Circuit] """ for pauli_string in operator._dict.keys(): if not pauli_string.map: continue copy = circ.copy() append_pauli_measurement(pauli_string, copy) yield copy