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Call

class Call(subroutine, value_dict=None, name=None)

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Bases: qiskit.pulse.instructions.instruction.Instruction

Pulse Call instruction.

The Call instruction represents the calling of a referenced subroutine (schedule). It enables code reuse both within the pulse representation and hardware (if supported).

Define new subroutine.

Note

Inline subroutine is mutable. This requires special care for modification.

Parameters

  • subroutine (Union[Schedule, ScheduleBlock]) – A program subroutine to be referred to.
  • value_dict (Optional[Dict[ParameterExpression, Union[ParameterExpression, float]]]) – Mapping of parameter object to assigned value.
  • name (Optional[str]) – Unique ID of this subroutine. If not provided, this is generated based on the subroutine name.

Raises

PulseError – If subroutine is not valid data format.


Methods

append

Call.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

Schedule

assign_parameters

Call.assign_parameters(value_dict)

Store parameters which will be later assigned to the subroutine.

Parameter values are not immediately assigned. The subroutine with parameters assigned according to the populated parameter table will be generated only when inline_subroutines() function is applied to this instruction. Note that parameter assignment logic creates a copy of subroutine to avoid the mutation problem. This function is usually applied by the Qiskit compiler when the program is submitted to the backend.

Parameters

value_dict (Dict[ParameterExpression, Union[ParameterExpression, float]]) – A mapping from Parameters to either numeric values or another Parameter expression.

Return type

Call

Returns

Self with updated parameters.

assigned_subroutine

Call.assigned_subroutine()

Returns this subroutine with the parameters assigned.

Note

This function may be often called internally for class equality check despite its overhead of parameter assignment. The subroutine with parameter assigned is cached based on .argument hash. Once this argument is updated, new assigned instance will be returned. Note that this update is not mutable operation.

Returns

Attached program.

Return type

program (Union[Schedule, ScheduleBlock])

ch_duration

Call.ch_duration(*channels)

Return duration of the supplied channels in this Instruction.

Parameters

*channels – Supplied channels

Return type

int

ch_start_time

Call.ch_start_time(*channels)

Return minimum start time for supplied channels.

Parameters

*channels – Supplied channels

Return type

int

ch_stop_time

Call.ch_stop_time(*channels)

Return maximum start time for supplied channels.

Parameters

*channels – Supplied channels

Return type

int

draw

Call.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

flatten

Call.flatten()

Return itself as already single instruction.

Return type

Instruction

insert

Call.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

Schedule

is_parameterized

Call.is_parameterized()

Return True iff the instruction is parameterized.

Return type

bool

shift

Call.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

Schedule


Attributes

arguments

Parameters dictionary to be assigned to subroutine.

Return type

Dict[ParameterExpression, Union[ParameterExpression, float]]

channels

Returns the channels that this schedule uses.

Return type

Tuple[Channel]

duration

Duration of this instruction.

Return type

Union[int, ParameterExpression]

id

Unique identifier for this instruction.

Return type

int

instructions

Iterable for getting instructions from Schedule tree.

Return type

Tuple[Tuple[int, Instruction]]

name

Name of this instruction.

Return type

str

operands

Return instruction operands.

Return type

Tuple

parameters

Unassigned parameters which determine the instruction behavior.

Return type

Set

prefix

Default value: 'call'

start_time

Relative begin time of this instruction.

Return type

int

stop_time

Relative end time of this instruction.

Return type

int

subroutine

Return attached subroutine.

Returns

The program referenced by the call.

Return type

program (Union[Schedule, ScheduleBlock])

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