this is an example of turning on selective G4 verbosity

this particular configuration will set G4 tracking verbosity

for every 2nd event (EventStep=2), for events from 0 to 6;

G4 tracking info printed for each 100th track (TrackStep=100),

for track numbers from 0 to 10000; if you wish, for example,

to print tracking info for every 10th track, set TrackStep=10,

or for each track - TrackStep=1

NOTE: don't forget to turn on VebosityLevel - otherwise only

info on the particle ID and track ID will be printed but nothing

on position, volume, etc.

For example usage, see also

SimG4Core/Application/test/runP-WithPionAndQGSP.cfg

TO USE:

in _cfg.py file:

process.g4SimHits.Watchers = cms.VPSet(cms.PSet(

CheckForHighEtPhotons = cms.untracked.bool(False),

G4Verbose = cms.untracked.bool(False),

EventMin = cms.untracked.int32(0),

EventMax = cms.untracked.int32(6),

EventStep = cms.untracked.int32(2),

TrackMin = cms.untracked.int32(0),

TrackMax = cms.untracked.int32(10000),

TrackStep = cms.untracked.int32(100),

VerboseLevel = cms.untracked.int32(1),

DEBUG = cms.untracked.bool(False),

PDGids = cms.untracked.vint32(),

type = cms.string('TrackingVerboseAction')

))