ignore_bad

sherpa.astro.ui.ignore_bad(id=None, bkg_id=None)

Exclude channels marked as bad in a PHA data set.

Ignore any bin in the PHA data set which has a quality value that is larger than zero.

Parameters:
  • id (int or str, optional) – The data set to change. If not given then the default identifier is used, as returned by get_default_id.
  • bkg_id (int or str, optional) – The identifier for the background (the default of None uses the first component).
Raises:

sherpa.utils.err.DataErr – If the data set has no quality array.

See also

ignore()
Exclude data from the fit.
notice()
Include data in the fit.
set_quality()
Apply a set of quality flags to a PHA data set.

Notes

The load_pha command - and others that create a PHA data set - do not exclude these bad-quality bins automatically.

If the data set has been grouped, then calling ignore_bad will remove any filter applied to the data set. If this happens a warning message will be displayed.

Examples

Remove any bins that are marked bad in the default data set:

>>> load_pha('src.pi')
>>> ignore_bad()

The data set ‘jet’ is grouped, and a filter applied. After ignoring the bad-quality points, the filter has been removed and will need to be re-applied:

>>> group_counts('jet', 20)
>>> notice_id('jet', 0.5, 7)
>>> get_filter('jet')
'0.540199995041:7.869399785995'
>>> ignore_bad('jet')
WARNING: filtering grouped data with quality flags, previous filters deleted
>>> get_filter('jet')
'0.200749998679:14.417500019073'