Plotting branches from different trees in same TFile

[isaacdl]

Hi, I’m tryiing to plot two histos in same canvas. There is one TFile objet, who has two trees (Wbb, ttvar) and each one has the branch HP_ENVERTEX_X. I’m only getting plotted one histo. What am i doing wrong?

Here is the code:

import ROOT
f=ROOT.TFile('MC_ntuples.root')


Wbb=f.Get('Wbb')
ttvar=f.Get('ttvar')

Wbb.Draw('HP_ENDVERTEX_X')
ttvar.Draw('HP_ENDVERTEX_X','same')

Thank you.

Got this error:

File "proba.py", line 11, in <module>
    ttvar.Draw('HP_ENDVERTEX_X','','same')
TypeError: void TObject::Draw(const char* option = "") =>
    takes at most 1 arguments (3 given)

[afiqaize]

Probably because ttvar has only 2 args, when at minimum 3 is needed to use “same”. Try with

ttvar.Draw("variable", "", "same")

Empty string in second arg just means no cut is applied.