Changes in the doc, change in the error message and in calling TSimpleAnalysis functions

main/python/rootdrawtree.py

 #!/usr/bin/env @python@
+
+# ROOT command line tools: rootdrawtree
+# Author: Luca Giommi
+# Mail: luca.giommi2@studio.unibo.it
+# Date: 08/09/16
+
 import ROOT
-import sys
 import argparse
-parser = argparse.ArgumentParser()
-parser.add_argument('inputFile', nargs='?', default='', help = "inputFile is the input file")
-parser.add_argument('-o', '--output', default='', action='store', dest='output', help='Output name')
-parser.add_argument('-r', '--root', default=[], nargs='*', dest='root', help='Input root files')
-parser.add_argument('-nt', '--ntuple', default='', action='store', dest='ntupla', help='Name of the ntuple')
-parser.add_argument('-hs', '--histo', default=[], nargs='*', dest='histoName', help='Expression to build histograms in the form "histoName=histo if histoCut"')
+import textwrap
+from sys import stderr
+
+parser = argparse.ArgumentParser(
+     formatter_class=argparse.RawDescriptionHelpFormatter,
+     description=textwrap.dedent('''\
+Python script that loops over a chain to create histograms.
+There are two ways to do it: one is parsing the name of the configuration file as argument,
+that must have a proper syntax as shown in the class documentation of TSimpleAnalysis.
+
+Example:
+user@users-desktop:~$ rootdrawtree input_file.txt   # input_file.txt is the configuration file
+
+The other way is to pass as arguments the name of the output file, the name of the .root input
+files, the expressions (that will be shown in the histograms) and the name of the tree (that
+is optional if there is only one tree inside the first .root input file).
+
+Examples:
+user@users-desktop:~$ rootdrawtree --output output.root --input hsimple.root --tree ntuple --histo 'hpxpy=px:py if px>2'
+user@users-desktop:~$ rootdrawtree --output output.root --input hsimple.root hsimple2.root --histo 'hpx=px' 'hpxpy=px:py if px>2'
+
+		'''))
+
+parser.add_argument('configFile', nargs='?', default='', help = "Configuration file")
+parser.add_argument('-o', '--output', default='', action='store', dest='output', help='Name of the output file in which will be stored the histograms')
+parser.add_argument('-i', '--input', default=[], nargs='*', dest='inputFiles', help='.root input files')
+parser.add_argument('-t', '--tree', default='', action='store', dest='tree', help='Name of the tree')
+parser.add_argument('-hs', '--histo', default=[], nargs='*', dest='histoExpr', help='Expressions to build the histograms in the form "NAME = EXPRESSION if CUT"')
 args = parser.parse_args()
-if (args.inputFile != '' and args.output=='' or args.root==[] or args.ntupla=='' or args.histoName==[]):
-	ROOT.gInterpreter.ProcessLine("#include \"TSimpleAnalysis.h\"")
-	ROOT.RunSimpleAnalysis(args.inputFile)
-elif (args.inputFile=='' and args.output!='' and args.root!=[] and args.ntupla!='' and args.histoName!=[]):
-	ROOT.gInterpreter.ProcessLine("#include \"TSimpleAnalysis.h\"")
-	inputfile=ROOT.vector("string")(len(args.root))
-	for i,s in enumerate(args.root):
-		inputfile[i]=s
-	expr=ROOT.vector("string")(len(args.histoName))
-	for k,l in enumerate(args.histoName):
-		expr[k]=l
-	a = ROOT.TSimpleAnalysis(args.output, inputfile, args.ntupla, expr)
+
+if (args.configFile != '' and (args.output != '' or args.inputFiles != [] or args.histoExpr != [] or args.tree != '')):
+	stderr.write("Error: both configuration file and options are provided \n")
+if (args.configFile != ''):
+	a = ROOT.TSimpleAnalysis(args.configFile)
+	a.Configure()
 	a.Run()
 else:
-	print "Invalid argument set"
+	inputfile = ROOT.vector("string")(len(args.inputFiles))
+	for i,s in enumerate(args.inputFiles):
+		inputfile[i] = s
+	expr = ROOT.vector("string")(len(args.histoExpr))
+	for k,l in enumerate(args.histoExpr):
+		expr[k]=l
+	a = ROOT.TSimpleAnalysis(args.output, inputfile, expr, args.tree)
+	a.Run()