C贸digo fuente para qiskit.pulse.instructions.play

# 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.

"""An instruction to transmit a given pulse on a ``PulseChannel`` (i.e., those which support
transmitted pulses, such as ``DriveChannel``).
from typing import Optional, Union, Tuple, Set

from qiskit.circuit.parameterexpression import ParameterExpression
from qiskit.pulse.channels import PulseChannel
from qiskit.pulse.exceptions import PulseError
from qiskit.pulse.instructions.instruction import Instruction
from qiskit.pulse.library.pulse import Pulse

[documentos]class Play(Instruction): """This instruction is responsible for applying a pulse on a channel. The pulse specifies the exact time dynamics of the output signal envelope for a limited time. The output is modulated by a phase and frequency which are controlled by separate instructions. The pulse duration must be fixed, and is implicitly given in terms of the cycle time, dt, of the backend. """ def __init__(self, pulse: Pulse, channel: PulseChannel, name: Optional[str] = None): """Create a new pulse instruction. Args: pulse: A pulse waveform description, such as :py:class:`~qiskit.pulse.library.Waveform`. channel: The channel to which the pulse is applied. name: Name of the instruction for display purposes. Defaults to ``pulse.name``. """ if name is None: name = pulse.name super().__init__(operands=(pulse, channel), name=name) def _validate(self): """Called after initialization to validate instruction data. Raises: PulseError: If pulse is not a Pulse type. PulseError: If the input ``channel`` is not type :class:`PulseChannel`. """ if not isinstance(self.pulse, Pulse): raise PulseError("The `pulse` argument to `Play` must be of type `library.Pulse`.") if not isinstance(self.channel, PulseChannel): raise PulseError(f"Expected a pulse channel, got {self.channel} instead.") @property def pulse(self) -> Pulse: """A description of the samples that will be played.""" return self.operands[0] @property def channel(self) -> PulseChannel: """Return the :py:class:`~qiskit.pulse.channels.Channel` that this instruction is scheduled on. """ return self.operands[1] @property def channels(self) -> Tuple[PulseChannel]: """Returns the channels that this schedule uses.""" return (self.channel,) @property def duration(self) -> Union[int, ParameterExpression]: """Duration of this instruction.""" return self.pulse.duration @property def parameters(self) -> Set: """Parameters which determine the instruction behavior.""" parameters = set() # Note that Pulse.parameters returns dict rather than set for convention. # We need special handling for Play instruction. for pulse_param_expr in self.pulse.parameters.values(): if isinstance(pulse_param_expr, ParameterExpression): parameters = parameters | pulse_param_expr.parameters if self.channel.is_parameterized(): parameters = parameters | self.channel.parameters return parameters