import ROOT
TDataFrame = ROOT.ROOT.Experimental.TDataFrame
def fill_tree(treeName, fileName):
d = TDataFrame(25000)
d.Define("px", "gRandom->Gaus()")\
.Define("py", "gRandom->Gaus()")\
.Define("pz", "sqrt(px * px + py * py)")\
.Snapshot(treeName, fileName)
fileName = "tdf003_profiles.root"
treeName = "myTree"
fill_tree(treeName, fileName)
columns = ROOT.vector('string')()
columns.push_back("px")
columns.push_back("py")
columns.push_back("pz")
d = TDataFrame(treeName, fileName, columns)
hprof1d = d.Profile1D(("hprof1d", "Profile of pz versus px", 64, -4, 4))
hprof2d = d.Profile2D(("hprof2d", "Profile of pz versus px and py", 40, -4, 4, 40, -4, 4, 0, 20))
c1 = ROOT.TCanvas("c1", "Profile histogram example", 200, 10, 700, 500)
hprof1d.Draw()
c2 = ROOT.TCanvas("c2", "Profile2D histogram example", 200, 10, 700, 500)
c2.cd()
hprof2d.Draw()