| AHELP for CIAO 4.5 Sherpa v1 | show_covar |
Context: info |
Synopsis
Display the covariance information
Syntax
show_covar([outfile=None, clobber=False] )
Description
The show_covar command displays the results of the covariance command ("ahelp covariance") .
- 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:
Covariance:Dataset = 1 Confidence Method = covariance Fitting Method = neldermead Statistic = cstat covariance 1-sigma (68.2689%) bounds: Param Best-Fit Lower Bound Upper Bound ----- -------- ----------- ----------- abs1.nh 0.0349312 -0.0108587 0.0108587 p1.gamma 1.72895 -0.0636437 0.0636437 p1.ampl 4.24936e-05 -2.19037e-06 2.19037e-06
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_covar()
Print the covariance information for all datasets to the screen.
Example 2
sherpa> show_covar("sherpa.covar", True)Write the covariance information to the file "sherpa.covar", clobbering any existing file with the same name.
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.
See Also
- filtering
- show_filter
- info
- list_bkg_ids, list_functions, show_all, show_bkg_model, show_bkg_source, show_conf, show_data, show_fit, show_method, show_model, show_proj, show_source, show_stat

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