# -*- coding: utf-8 -*-
# This code is part of Qiskit.
#
# (C) Copyright IBM 2020.
#
# 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.
"""Frequency instructions module. These instructions allow the user to manipulate
the frequency of a channel.
"""
from typing import Optional
from ..channels import PulseChannel
from .instruction import Instruction
[docs]class SetFrequency(Instruction):
r"""Set the channel frequency. This command operates on ``PulseChannel`` s.
A ``PulseChannel`` creates pulses of the form
.. math::
Re[\exp(i 2\pi f jdt + \phi) d_j].
Here, :math:`f` is the frequency of the channel. The command ``SetFrequency`` allows
the user to set the value of :math:`f`. All pulses that are played on a channel
after SetFrequency has been called will have the corresponding frequency.
The duration of SetFrequency is 0.
"""
def __init__(self, frequency: float,
channel: Optional[PulseChannel],
name: Optional[str] = None):
"""Creates a new set channel frequency instruction.
Args:
frequency: New frequency of the channel in Hz.
channel: The channel this instruction operates on.
name: Name of this set channel frequency command.
"""
self._frequency = float(frequency)
self._channel = channel
super().__init__((frequency, channel), 0, (channel,), name=name)
@property
def frequency(self) -> float:
"""New frequency."""
return self._frequency
@property
def channel(self) -> PulseChannel:
"""Return the :py:class:`~qiskit.pulse.channels.Channel` that this instruction is
scheduled on.
"""
return self._channel