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Last modified: December 2007

URL: http://cxc.harvard.edu/sherpabeta/set_stat.py.html
AHELP for Sherpa 4.0 Beta set_stat Context: py.sherpa

Synopsis

Set the current Sherpa statistic by name

Syntax

set_stat( stat )

Description

Set the current Sherpa statistic by name. The available statistics are:

Statistic Description
chi2constvar chi^2 with constant variance computed from the counts data
chi2modvar chi^2 with model amplitude variance
chi2gehrels chi^2 with gehrels method (default)
chi2datavar chi^2 with data variance
chi2xspecvar chi^2 with data variance (XSPEC-style, variance = 1.0 if data less than or equal to 0.0).
cstat CStat - A maximum likelihood function (XSPEC implementation of Cash)
cash Cash - A maximum likelihood function

Example

sherpa> set_stat( 'chi2modvar' )

Set the statistic to "chi2modvar", chi^2 with model amplitude variance.

Bugs

See the bugs pages on the Sherpa Beta website for an up-to-date listing of known bugs.

Last modified: December 2007



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