Chandra X-Ray Observatory
	(CXC)
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Last modified: December 2013

URL: http://cxc.harvard.edu/sherpa/ahelp/leastsq.html
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AHELP for CIAO 4.9 Sherpa v1

leastsq

Context: statistics

Synopsis

Chi-square statistic with variance set to 1.

Description

The leastsq statistic is equivalent to chi2constvar ("ahelp chi2constvar"), except the variance is always set to 1.

Example

sherpa> set_stat("leastsq")
sherpa> show_stat()

Set the fitting statistic and then confirm the new value.

Bugs

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

See Also

info
list_stats
statistics
cash, chi2constvar, chi2datavar, chi2gehrels, chi2modvar, chi2xspecvar, chisquare, cstat, get_prior, list_priors, set_prior, set_sampler, set_stat, wstat

Last modified: December 2013
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The Chandra X-Ray Center (CXC) is operated for NASA by the Smithsonian Astrophysical Observatory. 60 Garden Street, Cambridge, MA 02138 USA.   Email:   cxchelp@head.cfa.harvard.edu Smithsonian Institution, Copyright © 1998-2017. All rights reserved.