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--- root:pyroot_th1 [2017/07/11 15:44] – [Filling a histogram from a tree] iwn
+++ root:pyroot_th1 [2017/09/05 10:35] (current) – [Handling TH1 histograms] iwn
@@ Line 1: / Line 1: @@
+[[root:root|Getting started with ROOT]] -> [[root:pyroot|Useful pyROOT snippets]] → [[root:pyroot_th1|Handling TH1 histograms]]
 ====== Handling TH1 histograms ======
+[[https://root.cern.ch/doc/master/classTH1.html|Here]] is the class reference for ''TH1''.
 ===== Importing ROOT classes =====
-To use ''TH1D'' in ''python'', you can either do
+To use ''TH1D'' in ''python'', you can either only import a ''TH1D'' class:
 <code python>
 from ROOT import TH1D
 hist = TH1D("hist_name","hist_title",100,0,100)
 </code>
-or
+or //all// classes:
 <code python>
 from ROOT import * # loads all classes, and thus takes longer
 hist = TH1D("hist_name","hist_title",100,0,100)
 </code>
-or
+or only the ''ROOT'' module:
 <code python>
 import ROOT
@@ Line 62: / Line 67: @@
 gROOT.Macro("myfunctions.C+")
 ...
-tree.Draw("deltaR(eta1,phi1,eta2,phi2) >> hist_name")    # function defined in "myfunctions.C+"
+tree.Draw("deltaR(eta1,phi1,eta2,phi2) >> hist_name")    # deltaR     function defined in "myfunctions.C+"
-tree.Draw("pt1 >> hist_name","(pt>30)*weightEta1(eta1)") # function defined in "myfunctions.C+"
+tree.Draw("pt1 >> hist_name","(pt>30)*weightEta1(eta1)") # weightEta1 function defined in "myfunctions.C+"
 </code>

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