using namespace TMVA::Experimental; void tmva002_RDataFrameAsTensor() { // Creation of an RDataFrame with five entries filled with ascending numbers ROOT::RDataFrame df(5); auto df2 = df.Define("x", "1.f*rdfentry_").Define("y", "-1.f*rdfentry_"); // Convert content of columns to an RTensor object auto x = AsTensor(df2); std::cout << "RTensor from an RDataFrame:\n" << x << "\n\n"; // The utility also supports reading only a part of the RDataFrame and different // memory layouts. auto x2 = AsTensor(df2, {"x"}, MemoryLayout::ColumnMajor); std::cout << "RTensor from a single column of the RDataFrame:\n" << x2 << "\n\n"; }