df003_profiles¶

Use TProfiles with RDataFrame.

This tutorial illustrates how to use TProfiles in combination with the RDataFrame. See the documentation of TProfile and TProfile2D to better understand the analogy of this code with the example one.

Author: Danilo Piparo (CERN)
This notebook tutorial was automatically generated with ROOTBOOK-izer from the macro found in the ROOT repository on Monday, March 27, 2023 at 09:45 AM.

In [1]:

import ROOT

Welcome to JupyROOT 6.29/01

A simple helper function to fill a test tree: this makes the example stand-alone.

In [2]:

def fill_tree(treeName, fileName):
    d = ROOT.RDataFrame(25000)
    d.Define("px", "gRandom->Gaus()")\
     .Define("py", "gRandom->Gaus()")\
     .Define("pz", "sqrt(px * px + py * py)")\
     .Snapshot(treeName, fileName)

We prepare an input tree to run on

In [3]:

fileName = "df003_profiles_py.root"
treeName = "myTree"
fill_tree(treeName, fileName)

We read the tree from the file and create a RDataFrame.

In [4]:

d = ROOT.RDataFrame(treeName, fileName)

Create the profiles

In [5]:

hprof1d = d.Profile1D(("hprof1d", "Profile of pz versus px", 64, -4, 4), "px", "py")
hprof2d = d.Profile2D(("hprof2d", "Profile of pz versus px and py", 40, -4, 4, 40, -4, 4, 0, 20), "px", "py", "pz")

And Draw

In [6]:

c1 = ROOT.TCanvas("c1", "Profile histogram example", 200, 10, 700, 500)
hprof1d.Draw()
c1.SaveAs("df003_c1.png")

c2 = ROOT.TCanvas("c2", "Profile2D histogram example", 200, 10, 700, 500)
hprof2d.Draw()
c2.SaveAs("df003_c2.png")

print("Saved figures to df003_*.png")

Saved figures to df003_*.png

Info in <TCanvas::Print>: png file df003_c1.png has been created
Info in <TCanvas::Print>: png file df003_c2.png has been created

Draw all canvases

In [7]:

from ROOT import gROOT 
gROOT.GetListOfCanvases().Draw()