Plot Options

scqubits implements a number of routines for plotting a variety of viewgraphs, such as one-dimensional and two-dimensional qubit wavefunctions, plots of energy spectra as a function of an external parameter and more. These plot functions and methods take specific mandatory arguments which differ from case to case. In addition, each routine accepts a set of keyword arguments **kwargs which are used

  • for setting graphics options affecting the format of the plot, and

  • for prompting graphical output to be written to a file.

Supported options

The options supported by scqubits plotting routines fall into a few groups. First, any option that can be set on the side of Matplotlib via Axes.set_xxx(...) is accessible through the keyword xxx. For example, to employ Axes.set_xlim(0,10) one provides the keyword argument xlim=(0,10) to the scqubits plot function of interest. The second set of options is specific to scqubits. The most common Matplotlib options and the custom scqubits options are summarized here:

keyword

Description

xlim: (float,float)

Lower/upper bounds for x axis

ylim: (float,float)

Lower/upper bounds for y axis

ymax: float

Only set upper bound on y axis

xlabel: str

Label text for x axis

ylabel: str

Label text for y axis

title: str

Title for plot

figsize: (float, float)

Figure size in inches

fig_ax: (Figure, Axes)

If provided, plot is added to existing objects

filename: str

If provided, plot is written to file

A number of additional options falling in the Axes.set_xxx(...) category is available; consult the matplotlib.axes.Axes API documentation to see the complete list.

Matplotlib’s option grid is also supported and appropriately handled by scqubits. An argument that reads grid=xxx which is passed to an scqubits plotting command, is internally processed as Axes.grid(**xxx), if the xxx is a python dictionary, or as Axes.grid(xxx) otherwise.

There are also some plotting options that scqubits plotting routines directly pass to the appropriate Matplotlib plotting commands (such as plot or imshow). In the case of standard x vs y types of plots, these include:

keyword

Description

alpha: float or None

Set the alpha value used for blending

linestyle: str

Set linestyle from {‘-’, ‘–’, ‘-.’, ‘:’, ‘’, …}

linewidth: float

Set the linewidth in points

marker: str

Marker style

markersize: str

Markersize in points

scqubits plotting routines that internally use Matplotlib’s imshow command (such as ZeroPi.plot_wavefunction for example) support

keyword

Description

interpolation: str

Types of interpolation such (e.g. “spline16”, “bilinear”, etc.)

For a more detailed description of some of the above options, see Matplotlib’s documentation.

Returns of plot functions

Every scqubit routine for plotting returns a tuple (Figure, Axes) of Matplotlib objects. These can be used for further processing by the user. In Jupyter, lines calling plot routines can be ended with a ; to avoid the text output indicating the returned objects.