ratioplot2.py File Reference

Namespaces
	ratioplot2

Detailed Description

Example of a fit residual plot.

Creates a histogram filled with random numbers from a gaussian distribution and fits it with a standard gaussian function. The result is passed to the TRatioPlot constructor. Additionally, after calling TRatioPlot::Draw the upper and lower y axis titles are modified. Confidence interval bands are automatically drawn on the bottom (but can be disabled by draw option nobands. nspired by the tutorial of Paul Gessinger.

import ROOT

ROOT.gStyle.SetOptStat(0)

c1 = ROOT.TCanvas("c1", "fit residual simple")
h1 = ROOT.TH1D("h1", "h1", 50, -5, 5)

h1.FillRandom("gaus", 2000)
h1.Fit("gaus")
h1.GetXaxis().SetTitle("x")

rp1 = ROOT.TRatioPlot(h1)
rp1.Draw()
rp1.GetLowerRefYaxis().SetTitle("ratio")
rp1.GetUpperRefYaxis().SetTitle("entries")

c1.Update()

Author

Alberto Ferro

Definition in file ratioplot2.py.