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After creating it, I take a look at it in the data_test directory and make sure the permissions look good for psrel, basically that it is world readable. I also remove my write permission to make it read only.

Using psana

Short xtc file can also be created using psana module PSXtcOutput.XtcOutputModule as shown in the configuration file psana-reduce-xtc.cfg

[psana]
files = exp=xcsi0314:run=213
skip-events = 5
events = 10

modules = PSXtcOutput.XtcOutputModule 

[PSXtcOutput.XtcOutputModule]
dirName  = ./

This procedure can be launched by the command

psana -c psana-reduce-xtc.cfg

or with additional parameters

psana -c psana-reduce-xtc.cfg -s 5 -n 10 exp=xcsi0314:run=213

which creates reduced xtc file e524-r0213-s00-c00.xtcf in local directory.  In this example the number of skipped and selected events is controlled by the parameters skip-events and events, respectively. More sophisticated event selection can be done with psana filtering modules included in the list of modules before PSXtcOutput.XtcOutputModule, for example

[ImgAlgos.TimeStampFilter]
filterIsOn  = yes
print_bits  = 31
tsinterval  =  2012-02-06 153629 / 2012-02-06 153630

[ImgAlgos.EventNumberFilter]
filterIsOn    = yes
evtstring     = 10,20,30,90
print_bits    = 6

See psana - Module Catalog for more detail.

Make a Unit Test to Process Output

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