Use the Display action to inspect entry values.
This tutorial shows how to use the Display action
import ROOT
ROOT.gInterpreter.ProcessLine('''
unsigned long long y = 1;
int x = 1;
double w = 1;
double z = 1;
ROOT::RDataFrame df(10);
auto d = df.Define("y", [&y]() { return y *= 100; }) // A column with ulongs
.Define("x",
[&x]() {
return std::vector<int>({x++, x++, x++, x++});
}) // A column with four-elements collection
.Define("w", [&w]() { return w *= 1.8; }) // A column with doubles
.Define("z", [&z]() {
z *= 1.1;
return std::vector<std::vector<double>>({{z, ++z}, {z, ++z}, {z, ++z}});
}); // A column of matrices
''')
d = ROOT.d
d1 = d.Display("")
cols = ROOT.vector('string')(); cols.push_back("x"); cols.push_back("y");
d2 = d.Display(cols)
print("The following is the representation of all columns with the default nr of entries")
d1.Print()
print("\n\nThe following is the representation of two columns with the default nr of entries")
d2.Print()
- Date
- August 2018
- Authors
- Enrico Guiraud, Danilo Piparo, Enric Tejedor Saavedra (CERN), Massimo Tumolo (Politecnico di Torino)
Definition in file df024_Display.py.