Make an obscat

Makes an observation catalogue for the current mission and instrument. If no instrument is set, you will be prompted for one. You can keep one catalogue per instrument per session prefix, and they can be accessed by switching the instrument name.

The catalogue is composed of the values, from the primary header of each specified file, of the keywords listed in the parameter obslist (or in the file filename if obslist has the value @filename). For ASCA the obscat includes all the 'Modal' keywords present in the event files.

Make can also use a selection critereon on the keywords in obslist to filter the catalogue as it is made. This selection string is stored in the parameter cat_filt, and follows the same syntax as in the select command. If cat_filt = DEF then the default expression is used, which is, for the SIS,


and for the GIS,


If a datamode has been set, then the default filter will also include the datamode.

This observation catalogue is not deleted on exit from XSELECT. It is the user's responsibility to remake the catalogue if the contents of the data directory change. This means that you do not have to remake the catalogue every time you enter Xselect. Further if it is present, the choose and show obscat commands will act on the catalogue specified by the session prefix, and instrument name.

The user option for the make_inst allows the user to enter his/her own list string with which the catalogue will be created. The format is the same as for the ls command in UNIX.

You do not have to be in the directory which contains the data. You will be prompted for the directories containing the Event data. Further, if you end the directory string with a ?, e.g.

xsel > make obs " /asca/data? "

then you will be shown an ls of this directory and prompted for the data directory again.

The catalogue is automatically displayed once it is made. However, this feature can be toggled on and off with the command

xsel > set DUMPCAT

This is useful for scripts, since the prompt to page the catalogue is an Ftool prompt, and so cannot be read from the script file.

Additionally, the catalogues can be viewed using show obscat. Another parameter, displist, lists the columns to be displayed in both cases. Both these parameters understand the @filename syntax for indirection.

The point of making obslist and displist seperate parameters is that it may be convenient to put more information in the catalogue than you want to see listed.

Data files can be selected from the observation catalogue by number using the choose command, as an alternative to using read and typing in the filenames.

Further, the catalogue does not need to be remade from session to session, but can be accessed straightaway using choose.


xsel >  make <make_what> <cat_filt> <data_dir> <make_inst>


xsel >  make obs "/asca/data/100010"

xsel >  make obs "/asca/data/100010" sis0

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Last modified: Tuesday, 10-Jan-2023 11:03:01 EST

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