Use the Stats action to extract the statistics of a column.
Extract the statistics relative to RDataFrame columns and store them in TStatistic instances.
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 09:46 AM.
Create a data frame and add two columns: one for the values and one for the weight.
ROOT::RDataFrame r(256);
auto rr = r.Define("v", [](ULong64_t e){return e;}, {"rdfentry_"})
.Define("w", [](ULong64_t e){return 1./(e+1);}, {"v"});
Now extract the statistics, weighted, unweighted - with and without explicit types.
auto stats_eu = rr.Stats<ULong64_t>("v");
auto stats_ew = rr.Stats<ULong64_t, double>("v", "w");
auto stats_iu = rr.Stats("v");
auto stats_iw = rr.Stats("v", "w");
Now print them: they are all identical of course!
stats_eu->Print();
stats_ew->Print();
stats_iu->Print();
stats_iw->Print();
OBJ: TStatistic Mean = 127.5 +- 4.628 RMS = 74.045 Count = 256 Min = 0 Max = 255 OBJ: TStatistic Mean = 40.8 +- 12.86 RMS = 60.318 Count = 256 Min = 0 Max = 255 OBJ: TStatistic Mean = 127.5 +- 4.628 RMS = 74.045 Count = 256 Min = 0 Max = 255 OBJ: TStatistic Mean = 40.8 +- 12.86 RMS = 60.318 Count = 256 Min = 0 Max = 255
Draw all canvases
gROOT->GetListOfCanvases()->Draw()