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The software to analyze GLAST data is pretty complex. It involves several (similar) release packages (BeamtestRelease, EngineeringModel, GlastRelease and ScienceTools) and many different
release versions. In order to add more complexity to the issue, different release packages run with different root versions, and different programs might be running with different shell flavours. That implies that one needs to be careful when changing software package; the chances of working with a not properly set package (i.e. wrong libraries) are not negligible.
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