Quellcode für qiskit.circuit.library.standard_gates.global_phase

# This code is part of Qiskit.
# (C) Copyright IBM 2023.
# 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
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"""Global Phase Gate"""

from typing import Optional
import numpy
from qiskit.circuit.gate import Gate
from qiskit.circuit.quantumregister import QuantumRegister
from qiskit.circuit.quantumcircuit import QuantumCircuit
from qiskit.circuit.parameterexpression import ParameterValueType

[Doku]class GlobalPhaseGate(Gate): r"""The global phase gate (:math:`e^{i\theta}`). Can be applied to a :class:`~qiskit.circuit.QuantumCircuit` **Mathematical Representation:** .. math:: \text{GlobalPhaseGate}\ = \begin{pmatrix} e^{i\theta} \end{pmatrix} """ def __init__(self, phase: ParameterValueType, label: Optional[str] = None): """ Args: phase: The value of phase it takes. label: An optional label for the gate. """ super().__init__("global_phase", 0, [phase], label=label) def _define(self): q = QuantumRegister(0, "q") qc = QuantumCircuit(q, name=self.name, global_phase=self.params[0]) self.definition = qc
[Doku] def inverse(self): r"""Return inverted GLobalPhaseGate gate. :math:`\text{GlobalPhaseGate}(\lambda)^{\dagger} = \text{GlobalPhaseGate}(-\lambda)` """ return GlobalPhaseGate(-self.params[0])
def __array__(self, dtype=complex): """Return a numpy.array for the global_phase gate.""" theta = self.params[0] return numpy.array([[numpy.exp(1j * theta)]], dtype=dtype)