25 TFile f(
"df009_FromScratchVSTTree_classic.root",
"RECREATE");
26 TTree t(
"treeName",
"treeName");
31 for (
int i = 0; i < 10; ++i) {
57 df.Define(
"b1", [&
b]() {
return b++; })
58 .Define(
"b2",
"(int) b1 * b1")
59 .Snapshot(
"treeName",
"df009_FromScratchVSTTree_df.root");
62void df009_FromScratchVSTTree()
ROOT's RDataFrame offers a high level interface for analyses of data stored in TTrees,...
A ROOT file is a suite of consecutive data records (TKey instances) with a well defined format.
A TTree represents a columnar dataset.