Filling a histogram from an NTuple with '>>'

[Wile_E_Coyote]

Add gROOT->cd(); right before nt->Draw("fspt>>AA");.

tree->Draw does not work

Dear experts, I want to use “tree->Draw(“var>>hist”);” then draw the hist in a canvas. I have the code (1) and the root file (2) to be add ate line 13. I have a default canvas which appears, but nothing on the canvas that I asked line 104, 108 and 116. Do you see what is wrong? Regards (1) http://calpas.web.cern.ch/calpas/plot.cc (2) http://calpas.web.cern.ch/calpas/sumWeightsFromTree.root

BTW. When you post “source code” or “output” here, do remember to enclose them into two lines which contain just three characters ``` (see how your post has been edited above).