Code source de qiskit.circuit.measure
# This code is part of Qiskit.
#
# (C) Copyright IBM 2017.
#
# This code is licensed under the Apache License, Version 2.0. You may
# obtain a copy of this license in the LICENSE.txt file in the root directory
# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
#
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.
"""
Quantum measurement in the computational basis.
"""
import warnings
from qiskit.circuit.instruction import Instruction
from qiskit.circuit.exceptions import CircuitError
[docs]class Measure(Instruction):
"""Quantum measurement in the computational basis."""
def __init__(self):
"""Create new measurement instruction."""
super().__init__("measure", 1, 1, [])
[docs] def broadcast_arguments(self, qargs, cargs):
qarg = qargs[0]
carg = cargs[0]
if len(carg) == len(qarg):
for qarg, carg in zip(qarg, carg):
yield [qarg], [carg]
elif len(qarg) == 1 and carg:
for each_carg in carg:
yield qarg, [each_carg]
else:
raise CircuitError("register size error")
def measure(circuit, qubit, clbit):
"""Measure a quantum bit into classical bit.
.. deprecated:: Qiskit Terra 0.19
Use :meth:`.QuantumCircuit.measure` instead, either by calling
``circuit.measure(qubit, clbit)``, or if a full function is required, then
``QuantumCircuit.measure(circuit, qubit, clbit)``.
Args:
circuit (QuantumCircuit): the quantum circuit to attach the measurement to.
qubit (Union[Qubit, int]): the quantum bit to measure
clbit (Union[Clbit, int]): the classical bit to store the measurement result in.
Returns:
.InstructionSet: a handle to the created instruction.
Raises:
CircuitError: if either bit is not in the circuit, or is in a bad format.
"""
warnings.warn(
"The loose 'measure' function is deprecated as of Qiskit Terra 0.19, and will be removed"
" in a future release. Instead, you should call 'circuit.measure(qubit, clbit)', or if you"
" need a function, you can do `QuantumCircuit.measure(circuit, qubit, clbit)'.",
category=DeprecationWarning,
stacklevel=2,
)
return circuit.measure(qubit, clbit)