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Last modified: December 2010

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AHELP for CIAO 4.3 Sherpa v1


Context: info


Display the fit information


show_fit([outfile=None, clobber=False] )


The show_fit command displays the fit information for the source and/or background ("ahelp fit") .

  • outfile - name of the file in which to store the information
  • clobber - a Boolean switch which indicates whether or not the 'outfile' should be overwritten, if the file already exists; default=False

The command output looks like:

Optimization Method: NelderMead
name         = simplex
ftol         = 1.19209289551e-07
maxfev       = None
initsimplex  = 0
finalsimplex = 9
step         = None
iquad        = 1
verbose      = 0

Statistic: CStat

Fit:Dataset               = 1
Method                = neldermead
Statistic             = cstat
Initial fit statistic = 4115.59
Final fit statistic   = 470.277 at function evaluation 450
Data points           = 460
Degrees of freedom    = 457
Probability [Q-value] = 0.323838
Reduced statistic     = 1.02905
Change in statistic   = 3645.31
   abs1.nh        0.0349312
   p1.gamma       1.72895
   p1.ampl        4.24936e-05

The behavior of the screen output is determined by the user's $PAGER environment variable setting, which is usually a variant of "more." To disable paging within show_all() - i.e. print the entire contents, even if it scrolls offscreen - change this setting to "cat" before starting Sherpa:

unix% setenv PAGER cat

unix% sherpa

Example 1

sherpa> show_fit()

Print the fit information to the screen.

Example 2

sherpa> show_fit("", True)

Write the fit information to the file "", clobbering any existing file with the same name.


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

See Also

list_bkg_ids, list_functions, show_all, show_bkg_model, show_bkg_source, show_conf, show_covar, show_data, show_method, show_model, show_proj, show_source, show_stat

Last modified: December 2010
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