Rf 1 0 6_Plotdecoration

Basic functionality: adding boxes with parameters to RooPlots and decorating with arrows, etc...

Author: Clemens Lange, Wouter Verkerke (C++ version)
This notebook tutorial was automatically generated with ROOTBOOK-izer from the macro found in the ROOT repository on Sunday, July 05, 2020 at 08:17 AM.

In [ ]:
import ROOT

Set up model

Create observables

In [ ]:
x = ROOT.RooRealVar("x", "x", -10, 10)

Create Gaussian

In [ ]:
sigma = ROOT.RooRealVar("sigma", "sigma", 1, 0.1, 10)
mean = ROOT.RooRealVar("mean", "mean", -3, -10, 10)
gauss = ROOT.RooGaussian("gauss", "gauss", x, mean, sigma)

Generate a sample of 1000 events with sigma=3

In [ ]:
data = gauss.generate(ROOT.RooArgSet(x), 1000)

Fit pdf to data

In [ ]:
gauss.fitTo(data)

Plot p.d.f. and data

Overlay projection of gauss on data

In [ ]:
frame = x.frame(ROOT.RooFit.Name("xframe"), ROOT.RooFit.Title(
    "RooPlot with decorations"), ROOT.RooFit.Bins(40))
data.plotOn(frame)
gauss.plotOn(frame)

Add box with pdf parameters

Left edge of box starts at 55% of Xaxis)

In [ ]:
gauss.paramOn(frame, ROOT.RooFit.Layout(0.55))

Add box with data statistics

X size of box is from 55% to 99% of Xaxis range, of box is at 80% of Yaxis range)

In [ ]:
data.statOn(frame, ROOT.RooFit.Layout(0.55, 0.99, 0.8))

Add text and arrow

Add text to frame

In [ ]:
txt = ROOT.TText(2, 100, "Signal")
txt.SetTextSize(0.04)
txt.SetTextColor(ROOT.kRed)
frame.addObject(txt)

Add arrow to frame

In [ ]:
arrow = ROOT.TArrow(2, 100, -1, 50, 0.01, "|>")
arrow.SetLineColor(ROOT.kRed)
arrow.SetFillColor(ROOT.kRed)
arrow.SetLineWidth(3)
frame.addObject(arrow)

Persist frame with all decorations in ROOT file

In [ ]:
f = ROOT.TFile("rf106_plotdecoration.root", "RECREATE")
frame.Write()
f.Close()

To read back and plot frame with all decorations in clean root session do root> ROOT.TFile f("rf106_plotdecoration.root") root> xframe.Draw()

In [ ]:
c = ROOT.TCanvas("rf106_plotdecoration", "rf106_plotdecoration", 600, 600)
ROOT.gPad.SetLeftMargin(0.15)
frame.GetYaxis().SetTitleOffset(1.6)
frame.Draw()

c.SaveAs("rf106_plotdecoration.png")

Draw all canvases

In [ ]:
from ROOT import gROOT 
gROOT.GetListOfCanvases().Draw()