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This script lives in /reg/g/psdmin /sdf/group/lcls/ds/ana/tutorials/examplePythonpsana1_examples/nonAreaDetAccessepics.py.  The LCLS DAQ includes many slowly changing quantities (e.g. voltages, temperatures, motor positions) that are recorded with software called EPICS.  Also, many other non-area-detectors are not yet accessible with the simple "Detector" interface.We have plans to make all data accessible with the easier "Detector" interface, but until that is complete we support the following older forms of accessing detector informationcalled EPICS.  This example shows the use of a more complex "full name" and an easier "alias" (see device names).

Code Block
from psana import *
ds = DataSource('exp=xpptut15:run=59:smd')

evrFullNameepicsVarFullName = SourceDetector('DetInfo(NoDetector.0:Evr.0)HX2:DVD:GCC:01:PMON')
evrAliasNameepicsVarAlias = SourceDetector('evr0SampleTemp_GetA')
ebeamName =  Source('BldInfo(EBeam)')
es = ds.env().epicsStore()
for nevent,evt in enumerate(ds.events()):
    # these next two lines are equivalent (second one uses "alias" name)        
    evr = evt.get(EvrData.DataV4, evrFullNameprint(epicsVarFullName())
    evr = evt.get(EvrData.DataV4, evrAliasName)
    # now fetch ebeam BLD ("Beam Line Data")                                    
    ebeam = evt.get(Bld.BldDataEBeamV7, ebeamNameprint(epicsVarAlias())
    # now access one of the slower "epics variables"                            
    if evr is None or ebeam is None: continue
    print evr
    print ebeam
    print es.value('HX2:DVD:GCC:01:PMON')
    breakbreak

References