This tutorial is based on the ROOT files generated in the first step.

Fill multiple histograms from diffent inputs

• Different files

   harry.py -i gaussians.root gaussians1000.root -f gaussians -x var0
  

• Different trees

   harry.py -i gaussians3.root -f gaussians1 gaussians2 -x var0
  

• Different expressions

   harry.py -i gaussians3.root -f gaussians1 -x var0 var1