Xselect's files

Once you have chosen the data, the list of files chosen is stored, along with the associated HK and GTI files, by Xselect. All further operations will act on these files, or on product files made in the course of analysis, where that is appropriate.

Xselect has one workspace for product files (e.g. from the FAINT or the SELECT EVENT commands). When this is filled by some command, say FAINT, then Xselect will point to the files in it, rather than the original files. However, the original file list is not lost, so by clearing the workspace (done by CLEAR FAINT, if the workspace was filled by FAINT, and similarly for the other commands, or as a last resort by CLEAR WORKSPACE), you get back to your original selection.

It is important to note that there is only one workspace, so if you give two commands that both use the workspace, for example a FAINT command, and then a SELECT EVENTS, the results of the FAINT command will be used in the SELECT command, but then will be overwritten. If you want to retain these files, then you should do the following:

xsel >  faint  
xsel >  save faint  
xsel >  select events

The saved workspace is duplicated, so that Xselect can continue to operate on the copy it keeps. The saved workspace files can be reloaded later, using the read command. Because the workspace is duplicated in the SAVE FAINT command, if you are short on disk space, it is a good practice to save these files, clear the workspace, and then read them in again using the READ command.


There are also some commands which produce a single product event file that is automatically used in future extract commands, again without losing the original data list. The two examples of this are the SISCLEAN command, and the EXTRACT EVENTS command.

When you save this filtered event list, you will be given the option to read it back into Xselect. Doing this will clear the previous data, and reset the data directory to the current working directory.

Xselect also stores the extracted lightcurves, spectra and images until you decide to save them (e.g. with SAVE CURVE, ...). If you do not save them, however, they will be erased when you exit the session.

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Last modified: Thursday, 21-Apr-2022 15:45:13 EDT