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Last modified: 26 October 2016

URL: http://cxc.harvard.edu/sherpa/bugs/fake_pha.html

Bugs: fake_pha


Table of Contents

Bugs


Bugs

Some fake_pha simulations have incorrect fit parameters and an incorrect number of counts.

Multiplication of two integrated models, each with its own normalization, is not handled correctly. It results in incorrect fit parameters and an incorrect number of counts in fake_pha simulations.

get_source must be used to assign a previously assigned model to a fake_pha data set.

To assign a model to a fake_pha data set which was has been previously assigned to another data set in the current Sherpa session - for example,

python.sherpa> set_model(1, xspowerlaw.p1*xswabs.abs1)
python.sherpa> set_model(3, get_source(1))

where data set id=3 is the one to be used with fake_pha, then get_source must be used to assign model id=1 to the faked data set, not get_model.


Last modified: 26 October 2016
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