Snapshot
class Snapshot(label, snapshot_type='statevector', name=None)
Bases: qiskit.pulse.instructions.instruction.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 (
Optional[str]) – Snapshot name which defaults tolabel. This parameter is only for display purposes and is not taken into account during comparison.
Raises
PulseError – If snapshot label is invalid.
Methods
append
Snapshot.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 (
Optional[str]) – Name of the new schedule. Defaults to name of self
Returns
A new schedule with schedule a this instruction at t=0.
Return type
ch_duration
Snapshot.ch_duration(*channels)
Return duration of the supplied channels in this Instruction.
Parameters
*channels – Supplied channels
Return type
int
ch_start_time
Snapshot.ch_start_time(*channels)
Return minimum start time for supplied channels.
Parameters
*channels – Supplied channels
Return type
int
ch_stop_time
Snapshot.ch_stop_time(*channels)
Return maximum start time for supplied channels.
Parameters
*channels – Supplied channels
Return type
int
draw
Snapshot.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.
Parameters
- dt (
float) – Time interval of samples - style (Optional[SchedStyle]) – A style sheet to configure plot appearance
- filename (
Optional[str]) – Name required to save pulse image - interp_method (
Optional[Callable]) – A function for interpolation - scale (
float) – Relative visual scaling of waveform amplitudes - plot_all (
bool) – Plot empty channels - plot_range (
Optional[Tuple[float]]) – 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 (
Optional[List[Channel]]) – A list of channel names to plot
Returns
A matplotlib figure object of the pulse schedule
Return type
matplotlib.figure
insert
Snapshot.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 (
Optional[str]) – 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
is_parameterized
Snapshot.is_parameterized()
Return True iff the instruction is parameterized.
Return type
bool
shift
Snapshot.shift(time, name=None)
Return a new schedule shifted forward by time.
Parameters
- time (
int) – Time to shift by - name (
Optional[str]) – Name of the new schedule. Defaults to name of self
Returns
The shifted schedule.
Return type
Attributes
channel
Return the Channel that this instruction is scheduled on; trivially, a SnapshotChannel.
Return type
channels
duration
Duration of this instruction.
Return type
int
id
Unique identifier for this instruction.
Return type
int
instructions
Iterable for getting instructions from Schedule tree.
Return type
Tuple[Tuple[int, Instruction]]
label
Label of snapshot.
Return type
str
name
Name of this instruction.
Return type
str
operands
Return instruction operands.
Return type
Tuple
parameters
Parameters which determine the instruction behavior.
Return type
Set
start_time
Relative begin time of this instruction.
Return type
int
stop_time
Relative end time of this instruction.
Return type
int
type
Type of snapshot.
Return type
str