Snapshot#

class qiskit.pulse.instructions.Snapshot(label, snapshot_type='statevector', name=None)[source]#

Bases: Instruction

An instruction targeted for simulators, to capture a moment in the simulation.

Create new snapshot.

Parameters:

  • label (str) -- Snapshot label which is used to identify the snapshot in the output.

  • snapshot_type (str) -- Type of snapshot, e.g., “state” (take a snapshot of the quantum state). The types of snapshots offered are defined by the simulator used.

  • name (str | None) -- Snapshot name which defaults to label. This parameter is only for display purposes and is not taken into account during comparison.

Attributes

channel#

Return the Channel that this instruction is scheduled on; trivially, a SnapshotChannel.

channels#

Returns the channels that this schedule uses.

duration#

Duration of this instruction.

id#

Unique identifier for this instruction.

instructions#

Iterable for getting instructions from Schedule tree.

label#

Label of snapshot.

name#

Name of this instruction.

operands#

Return instruction operands.

parameters#

Parameters which determine the instruction behavior.

start_time#

Relative begin time of this instruction.

stop_time#

Relative end time of this instruction.

type#

Type of snapshot.

Methods

append(schedule, name=None)#

Return a new Schedule with schedule inserted at the maximum time over all channels shared between self and schedule.

Parameters:

  • schedule (Union['Schedule', 'Instruction']) -- Schedule or instruction to be appended

  • name (str | None) -- Name of the new schedule. Defaults to name of self

Returns:

A new schedule with schedule a this instruction at t=0.

Return type:

Schedule

ch_duration(*channels)#

Return duration of the supplied channels in this Instruction.

Parameters:

*channels (List[Channel]) -- Supplied channels

Return type:

int

ch_start_time(*channels)#

Return minimum start time for supplied channels.

Parameters:

*channels (List[Channel]) -- Supplied channels

Return type:

int

ch_stop_time(*channels)#

Return maximum start time for supplied channels.

Parameters:

*channels (List[Channel]) -- Supplied channels

Return type:

int

draw(dt=1, style=None, filename=None, interp_method=None, scale=1, plot_all=False, plot_range=None, interactive=False, table=True, label=False, framechange=True, channels=None)#

Plot the instruction.

Deprecated since version 0.23.0: The method qiskit.pulse.instructions.instruction.Instruction.draw() is deprecated as of qiskit-terra 0.23.0. It will be removed no earlier than 3 months after the release date. No direct alternative is being provided to drawing individual pulses. But, instructions can be visualized as part of a complete schedule using qiskit.visualization.pulse_drawer.

Parameters:

  • dt (float) -- Time interval of samples

  • style (Optional[SchedStyle]) -- A style sheet to configure plot appearance

  • filename (str | None) -- Name required to save pulse image

  • interp_method (Callable | None) -- A function for interpolation

  • scale (float) -- Relative visual scaling of waveform amplitudes

  • plot_all (bool) -- Plot empty channels

  • plot_range (Tuple[float] | None) -- A tuple of time range to plot

  • interactive (bool) -- When set true show the circuit in a new window (this depends on the matplotlib backend being used supporting this)

  • table (bool) -- Draw event table for supported instructions

  • label (bool) -- Label individual instructions

  • framechange (bool) -- Add framechange indicators

  • channels (List[Channel] | None) -- A list of channel names to plot

Returns:

A matplotlib figure object of the pulse schedule

Return type:

matplotlib.figure

insert(start_time, schedule, name=None)#

Return a new Schedule with schedule inserted within self at start_time.

Parameters:

  • start_time (int) -- Time to insert the schedule schedule

  • schedule (Union['Schedule', 'Instruction']) -- Schedule or instruction to insert

  • name (str | None) -- Name of the new schedule. Defaults to name of self

Returns:

A new schedule with schedule inserted with this instruction at t=0.

Return type:

Schedule

is_parameterized()[source]#

Return True iff the instruction is parameterized.

Return type:

bool

shift(time, name=None)#

Return a new schedule shifted forward by time.

Parameters:

  • time (int) -- Time to shift by

  • name (str | None) -- Name of the new schedule. Defaults to name of self

Returns:

The shifted schedule.

Return type:

Schedule