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Reference Guide
example.py File Reference

Namespaces

namespace  example
 

Detailed Description

A ROOT script demonstrating an example of writing a HistFactory model using Python.

def main():
try:
import ROOT
except:
print("It seems that pyROOT isn't properly configured")
return
"""
Create a HistFactory measurement from python
"""
InputFile = "./data/example.root"
if (ROOT.gSystem.AccessPathName(InputFile)) :
ROOT.Info("example.py", InputFile+" does not exist")
exit()
# Create the measurement
meas = ROOT.RooStats.HistFactory.Measurement("meas", "meas")
meas.SetOutputFilePrefix( "./results/example_UsingPy" )
meas.SetPOI( "SigXsecOverSM" )
meas.AddConstantParam("Lumi")
meas.AddConstantParam("alpha_syst1")
meas.SetLumi( 1.0 )
meas.SetLumiRelErr( 0.10 )
meas.SetExportOnly( False )
# Create a channel
chan = ROOT.RooStats.HistFactory.Channel( "channel1" )
chan.SetData( "data", InputFile )
chan.SetStatErrorConfig( 0.05, "Poisson" )
# Now, create some samples
# Create the signal sample
signal = ROOT.RooStats.HistFactory.Sample( "signal", "signal", InputFile )
signal.AddOverallSys( "syst1", 0.95, 1.05 )
signal.AddNormFactor( "SigXsecOverSM", 1, 0, 3 )
chan.AddSample( signal )
# Background 1
background1 = ROOT.RooStats.HistFactory.Sample( "background1", "background1", InputFile )
background1.ActivateStatError( "background1_statUncert", InputFile )
background1.AddOverallSys( "syst2", 0.95, 1.05 )
chan.AddSample( background1 )
# Background 1
background2 = ROOT.RooStats.HistFactory.Sample( "background2", "background2", InputFile )
background2.ActivateStatError()
background2.AddOverallSys( "syst3", 0.95, 1.05 )
chan.AddSample( background2 )
# Done with this channel
# Add it to the measurement:
meas.AddChannel( chan )
# Collect the histograms from their files,
# print some output,
meas.CollectHistograms()
meas.PrintTree();
# One can print XML code to an
# output directory:
# meas.PrintXML( "xmlFromCCode", meas.GetOutputFilePrefix() );
meas.PrintXML( "xmlFromPy", meas.GetOutputFilePrefix() );
# Now, do the measurement
ROOT.RooStats.HistFactory.MakeModelAndMeasurementFast( meas );
pass
if __name__ == "__main__":
main()
int main(int argc, char *argv[])
Definition: cef_main.cxx:54
Author
George Lewis

Definition in file example.py.