Df 0 0 8_Create Data Set From Scratch

Create data from scratch with RDataFrame.

This tutorial shows how to create a dataset from scratch with RDataFrame

Author: Danilo Piparo (CERN)
This notebook tutorial was automatically generated with ROOTBOOK-izer from the macro found in the ROOT repository on Tuesday, June 15, 2021 at 07:16 AM.

We create an empty data frame of 100 entries

In [1]:
ROOT::RDataFrame df(100);

We now fill it with random numbers

In [2]:
gRandom->SetSeed(1);
auto df_1 = df.Define("rnd", []() { return gRandom->Gaus(); });

And we write out the dataset on disk

In [3]:
df_1.Snapshot("randomNumbers", "df008_createDataSetFromScratch.root");