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The software to analyze GLAST data is pretty complex. It involves several (similar but with subtle differences)
release packages 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.
In this section you can find a set of scripts and a root macro that help setting the environment variables variables
in a more or less systematic and controlled way.
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