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Reference Guide
mrt.py File Reference


namespace  mrt

Detailed Description

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This program reads the ‘aptuple.txt’ file row by row, then creates the Ntuple by adding row by row.

import sys, os
from ROOT import TFile, TNtuple, TROOT
ifn = os.path.join(str(TROOT.GetTutorialDir()), 'pyroot', 'aptuple.txt')
ofn = 'aptuple.root'
print('opening file %s ...' % ifn)
infile = open( ifn, 'r' )
lines = infile.readlines()
title = lines[0]
labels = lines[1].split()
print('writing file %s ...' % ofn)
outfile = TFile( ofn, 'RECREATE', 'ROOT file with an NTuple' )
ntuple = TNtuple( 'ntuple', title, ':'.join( labels ) )
for line in lines[2:]:
words = line.split()
row = map( float, words )
A ROOT file is a suite of consecutive data records (TKey instances) with a well defined format.
Definition: TFile.h:54
A simple TTree restricted to a list of float variables only.
Definition: TNtuple.h:28
static const TString & GetTutorialDir()
Get the tutorials directory in the installation. Static utility function.
Definition: TROOT.cxx:3027
Wim Lavrijsen

Definition in file mrt.py.