get_bkg_plot

sherpa.astro.ui.get_bkg_plot(id: IdType | None = None, bkg_id: IdType | None = None, recalc: bool = True, copy: bool = True)

Return the data used by plot_bkg.

Changed in version 4.19.0: The plot object is now copied by default. To get the previous behaviour set the copy attribute to False.

Parameters:

idint, str, or None, optional

The data set that provides the data. If not given then the default identifier is used, as returned by get_default_id.

bkg_idint, str, or None, optional

Identify the background component to use, if there are multiple ones associated with the data set.

recalcbool, optional

If False then the results from the last call to plot_bkg (or get_bkg_plot) are returned, otherwise the data is re-generated.

copybool, optional

Is the plot object copied before being returned? If so then the plot attributes will not be changed by multiple calls to this routine.

Returns:

dataa sherpa.astro.plot.BkgDataPlot instance

An object representing the data used to create the plot by plot_data. The relationship between the returned values and the values in the data set depend on the analysis, filtering, and grouping settings of the data set.

Raises:

sherpa.utils.err.ArgumentErr

If the data set does not contain PHA data.

sherpa.utils.err.IdentifierErr

If the bkg_id parameter is invalid.

See also

get_default_id

Return the default data set identifier.

plot_bkg

Plot the background values for a PHA data set.

Examples

Create the data needed to create the “data plot” for the background of the default data set and display it:

>>> bplot = get_bkg_plot()
>>> print(bplot)

Return the plot data for data set 2, and then use it to create a plot:

>>> b2 = get_bkg_plot(2)
>>> b2.plot()

Return the plot data for the second background component to the “jet” data set:

>>> bplot = get_bkg_plot('jet', bkg_id=2)