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Last modified: December 2006

URL: http://cxc.harvard.edu/ciao3.4/record.html
Hardcopy (PDF): A4 | Letter
AHELP for CIAO 3.4 record Context: sherpa

Synopsis

Controls output of parameters values and statistics to an ASCII file.

Syntax

sherpa> RECORD [{ON | OFF}]

Description

During every iteration of a fit, points in parameter space are chosen and statistics computed. The user can access information about these intermediate fits by issuing the command RECORD ON and retrieving the contents of the file described below. RECORD OFF turns off the recording. Issuing the command RECORD alone causes Sherpa to display the current setting.

Fit information is written to the ASCII file search-<username>.dat, located the $ASCDS_WORK_PATH directory; type "echo $ASCDS_WORK_PATH" to find the location on your system.

Note that successive FIT commands cause the file contents to be overwritten!

The fit information may also be accessed via the Sherpa/S-Lang module function get_record.

Example

Write fit parameter values and statistics to an ASCII file:

sherpa> PARAMPROMPT OFF
Model parameter prompting is off
sherpa> DATA data/example1.dat
sherpa> POLYNOM1D[my]
sherpa> THAW my.c1 my.c2
sherpa> SOURCE 1 = my
sherpa> METHOD SIMPLEX
sherpa> RECORD ON
sherpa> FIT
 smplx: v1.3
 smplx:  initial statistic value =     3.25453E+02
 smplx:     converged to minimum =     3.44058E-01 at iteration =     82
 smplx:    final statistic value =     3.44058E-01
            my.c0  -0.996019     
            my.c1  0.672607     
            my.c2  0.923389     

sherpa> $echo $ASCDS_WORK_PATH
/tmp
sherpa> $ls /tmp/search*
/tmp/search-<username>dat
sherpa> $more /tmp/search-<username>.dat
my.c0   my.c1   my.c2   Chi-Squared
33   0   0   325.453
33   0   0   325.453
32.34   0.01   0.01   312.682
32.34   0.01   0.01   312.682
31.9   0.00666667   0.00333333   303.974
...

Bugs

See the Sherpa bug pages online for an up-to-date listing of known bugs.

Hardcopy (PDF): A4 | Letter
Last modified: December 2006



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