sherpa.astro.ui.set_backscal(id, backscale=None, bkg_id=None)

Change the area scaling of a PHA data set.

The area scaling factor of a PHA data set is taken from the BACKSCAL keyword or column, but it can be changed once the file has been loaded.

  • id (int or str, optional) – The identifier for the data set to use. If not given then the default identifier is used, as returned by get_default_id.

  • backscale (number or array) – The scaling factor.

  • bkg_id (int or str, optional) – Set to identify which background component to set. The default value (None) means that this is for the source component of the data set.

See also


Return the area scaling of a PHA data set.


Change the fractional area factor of a PHA data set.


Change the exposure time of a PHA data set.


The function does not follow the normal Python standards for parameter use, since it is designed for easy interactive use. When called with a single un-named argument, it is taken to be the backscale parameter. If given two un-named arguments, then they are interpreted as the id and backscale parameters, respectively. The remaining parameters are expected to be given as named arguments.