get_bkg_delchi_plot

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

Return the data used by plot_bkg_delchi.

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_delchi (or get_bkg_delchi_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:

delchia sherpa.astro.plot.BkgDelchiPlot instance

An object representing the data used to create the plot by plot_bkg_delchi.

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.

sherpa.utils.err.ModelErr

If no model expression has been created for the background data.

See also

get_bkg_chisqr_plot

Return the data used by plot_bkg_chisqr.

get_bkg_ratio_plot

Return the data used by plot_bkg_ratio.

get_bkg_resid_plot

Return the data used by plot_bkg_resid.

plot_bkg_delchi

Plot the ratio of residuals to error for the background of a PHA data set.

Examples

>>> bplot = get_bkg_delchi_plot()
>>> print(bplot)

>>> get_bkg_delchi_plot('jet', bkg_id=1).plot()
>>> get_bkg_delchi_plot('jet', bkg_id=2).overplot()