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Making Selections

The user can also apply selection criteria to the data itself, as well as the HK or auxiliary filter files, to filter the data. There are two provisions for selections based on data:

a) To apply a general selection expression based on the columns in the event files, use the command

xsel >  select event

This command produces a set of reduced events files, one for each input file, which are stored in the workspace. To save these files, use

xsel > save select

To aid in building up these expressions, the command

xsel >  show params event

will display the column names in the event list files. You can also use the command

xsel > show event

to look at the event data itself.

b) To apply a selection based on the columns of the auxiliary filter files, use the command

xsel >  select mkf

To see the columns available in the auxiliary files, use the command

xsel >  show parameters mkf

To gain insight into the behavior of these parameters, use the commands

xsel > mkfbin
xsel > plot mkf

The first will bin up a user supplied list of the mkf parameters. The second will plot up these binned curves. They can be plotted either against time, or against each other. If an event lightcurve has been extracted then this can also be plotted with the mkf parameters to look for correlations between the event rate and other information.


next up previous contents
Next: Saving clearing and setting Up: Overview Previous: Entering Filters
Keith Arnaud
2006-07-26


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Last modified: Monday, 19-Mar-2012 14:16:45 EDT