Adding Analysis Routines to SAOtng

Each file type known to SAOtng can have user-defined analysis commands associated with it. These analysis commands are defined at start-up time by means of ASCII descriptions. The analysis commands associated with the currently displayed image are available for execution, either via an analysis menu in the SAOtng GUI or using SAOtng's XPA "analysis" command. When activated, an analysis command first is macro-expanded to fill in user-defined arguments and then is executed externally using the system() function (see Macro expansion in SAOtng. Results can be displayed in a separate window or even can be sent back to SAOtng, i.e., an analysis command can create an image and send it to SAOtng for display:

  xpaget SAOtng $data | smooth ... | xpaset SAOtng "frame new"

In the example above, the FITS representation of the currently displayed image in SAOtng is piped into the standard input of an image smoothing program. The FITS image generated by this program then is piped back into a new frame buffer of SAOtng for display.

The ASCII file that defines the known image files consists of one or more file descriptors, each of which has the following format:

A help line describing the file types
A space-separated list of templates
A space-separated list of file types (not currently used)
The command line for the analysis program

Note that blank lines separate the file descriptions and should not be used as part of a description. Also, the '#' character is a comment character.

For example, the default analysis file currently contains the following:

#
# Analysis command descriptions:
#	help
#	file templates
#	file types
#	analysis command line

counts -- number of events in region (no background)
*.qp *.imh 
QPOE IMH
uiraf '${xraybin}'/x_xspatial.e imcnts source='${filename}' region=$sregion bkgd=0 table=NONE | XText -title ${filename}_imcnts

counts w/bkgd  -- number of events in region with background subtraction
*.qp *.imh
QPOE IMH
uiraf '${xraybin}'/x_xspatial.e imcnts source='${filename}' region=$sregion bkgd='${filename}' bkgdregion=$bregion table=NONE | XText -title ${filename}_imcnts

minmax -- calculate the min and max of the entire QPOE file
*.qp *.imh
QPOE IMH
uiraf '${bin}'/x_images.e minmax image='${filename}' update=yes verbose=no | XText -title ${filename}_minmax

minmax -- calculate the min and max of the current image section
*
FITS
$data | fminmax | XText -title ${filename}_minmax

New analysis routines are added to SAOtng using the -analysis [analysis prog list] option on the command line. The files in the file list are then added to the system-support routines.

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Last Updated May 1, 1995