ROOT
6.12/07
Reference Guide
tutorials
dataframe
tdf008_createDataSetFromScratch.C
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/// \file
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/// \ingroup tutorial_tdataframe
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/// \notebook -nodraw
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/// This tutorial shows how to create a dataset from scratch with TDataFrame
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/// \macro_code
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///
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/// \date June 2017
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/// \author Danilo Piparo
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void
tdf008_createDataSetFromScratch
()
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{
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// We create an empty data frame of 100 entries
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ROOT::Experimental::TDataFrame
tdf(100);
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// We now fill it with random numbers
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gRandom
->
SetSeed
(1);
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auto
tdf_1 = tdf.Define(
"rnd"
, []() {
return
gRandom
->
Gaus
(); });
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// And we write out the dataset on disk
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tdf_1.Snapshot(
"randomNumbers"
,
"tdf008_createDataSetFromScratch.root"
);
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}
TRandom::Gaus
virtual Double_t Gaus(Double_t mean=0, Double_t sigma=1)
Samples a random number from the standard Normal (Gaussian) Distribution with the given mean and sigm...
Definition:
TRandom.cxx:256
TRandom::SetSeed
virtual void SetSeed(ULong_t seed=0)
Set the random generator seed.
Definition:
TRandom.cxx:589
gRandom
R__EXTERN TRandom * gRandom
Definition:
TRandom.h:62
tdf008_createDataSetFromScratch
Definition:
tdf008_createDataSetFromScratch.py:1
ROOT::Experimental::TDataFrame
ROOT's TDataFrame offers a high level interface for analyses of data stored in TTrees.
Definition:
TDataFrame.hxx:39