sherpa.astro.xspec.set_xsxset(name, value)[source] [edit on github]

Set a X-Spec model setting.

Set variables used by X-Spec models. It is equivalent to the X-Spec xset command 1, but only for setting the model database settings. See set_xsabund, set_xscosmo, and set_xsxsect for the other settings.

  • name (str) – The name of the setting. It is converted to upper case before being used. There is no check that the name is valid.

  • value (str) – The new value of the setting. It must be given as a string.


The available settings are listed at 1. Not all the X-Spec model types are supported by Sherpa - for instance X-Spec “mixing models” - so changing some of these settings will make no difference. The X-Spec chatter setting can be increased with set_xschatter if it is not clear if a setting is being used.

The model settings are stored so that they can be included in the output of sherpa.astro.ui.save_all.


1(1,2) Note that this may refer to a newer version than the compiled version used by Sherpa; use get_xsversion to check.


>>> set_xsxset('NEIVERS', '2.0')
>>> set_xsxset('NEIAPECROOT', '/data/spectral/modelData/APEC_nei_v11')
>>> set_xsxset('POW_EMIN', '0.5')
>>> set_xsxset('POW_EMAX', '2.0')