class qiskit.pulse.library.ScalableSymbolicPulse(pulse_type, duration, amp, angle, parameters=None, name=None, limit_amplitude=None, envelope=None, constraints=None, valid_amp_conditions=None)[source]#

Bases: SymbolicPulse

Subclass of SymbolicPulse for pulses with scalable envelope.

Instance of ScalableSymbolicPulse behaves the same as an instance of SymbolicPulse, but its envelope is assumed to have a scalable form \(\text{amp}\times\exp\left(i\times\text{angle}\right)\times\text{F} \left(t,\text{parameters}\right)\), where \(\text{F}\) is some function describing the rest of the envelope, and both amp and angle are real (float). Note that both amp and angle are stored in the parameters dictionary of the ScalableSymbolicPulse instance.

When two ScalableSymbolicPulse objects are equated, instead of comparing amp and angle individually, only the complex amplitude :math:’text{amp}timesexpleft(itimestext{angle}right)’ is compared.

Create a scalable symbolic pulse.

Deprecated since version 0.25.0: Setting amp to a complex in the ScalableSymbolicPulse constructor is deprecated as of qiskit-terra 0.25.0. It will be removed no earlier than 3 months after the release date. Instead, use a float for amp (for the magnitude) and a float for angle

  • pulse_type (str) – Display name of this pulse shape.

  • duration (ParameterExpression | int) – Duration of pulse.

  • amp (ParameterExpression | float) – The magnitude of the complex amplitude of the pulse.

  • angle (ParameterExpression | float) – The phase of the complex amplitude of the pulse.

  • parameters (Dict[str, ParameterExpression | complex] | None) – Dictionary of pulse parameters that defines the pulse envelope.

  • name (str | None) – Display name for this particular pulse envelope.

  • limit_amplitude (bool | None) – If True, then limit the absolute value of the amplitude of the waveform to 1. The default is True and the amplitude is constrained to 1.

  • envelope (Expr | None) – Pulse envelope expression.

  • constraints (Expr | None) – Pulse parameter constraint expression.

  • valid_amp_conditions (Expr | None) – Extra conditions to skip a full-waveform check for the amplitude limit. If this condition is not met, then the validation routine will investigate the full-waveform and raise an error when the amplitude norm of any data point exceeds 1.0. If not provided, the validation always creates a full-waveform.


PulseError – If both amp is complex and angle is not None or 0.



Return symbolic expression for the pulse parameter constraints.


Return symbolic expression for the pulse envelope.


Unique identifier for this pulse.

limit_amplitude = True#

Return display name of the pulse shape.


Return symbolic expression for the pulse amplitude constraints.


draw(style=None, backend=None, time_range=None, time_unit='dt', show_waveform_info=True, plotter='mpl2d', axis=None)#

Plot the interpolated envelope of pulse.

  • style (Dict[str, Any] | None) – Stylesheet options. This can be dictionary or preset stylesheet classes. See IQXStandard, IQXSimple, and IQXDebugging for details of preset stylesheets.

  • backend (Optional[BaseBackend]) – Backend object to play the input pulse program. If provided, the plotter may use to make the visualization hardware aware.

  • time_range (Tuple[int, int] | None) – Set horizontal axis limit. Tuple (tmin, tmax).

  • time_unit (str) – The unit of specified time range either dt or ns. The unit of ns is available only when backend object is provided.

  • show_waveform_info (bool) – Show waveform annotations, i.e. name, of waveforms. Set True to show additional information about waveforms.

  • plotter (str) –

    Name of plotter API to generate an output image. One of following APIs should be specified:

    mpl2d: Matplotlib API for 2D image generation.
        Matplotlib API to generate 2D image. Charts are placed along y axis with
        vertical offset. This API takes matplotlib.axes.Axes as `axis` input.

    axis and style kwargs may depend on the plotter.

  • axis (Any | None) – Arbitrary object passed to the plotter. If this object is provided, the plotters use a given axis instead of internally initializing a figure object. This object format depends on the plotter. See plotter argument for details.


Visualization output data. The returned data type depends on the plotter. If matplotlib family is specified, this will be a matplotlib.pyplot.Figure data.


Return a Waveform with samples filled according to the formula that the pulse represents and the parameter values it contains.

Since the returned array is a discretized time series of the continuous function, this method uses a midpoint sampler. For duration, return:

\[\{f(t+0.5) \in \mathbb{C} | t \in \mathbb{Z} \wedge 0<=t<\texttt{duration}\}\]

A waveform representation of this pulse.

  • PulseError – When parameters are not assigned.

  • PulseError – When expression for pulse envelope is not assigned.

Return type:



Return True iff the instruction is parameterized.

Return type:



Validate parameters.


PulseError – If the parameters passed are not valid.