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Revision c773da9f5b81c15a00fec29ca0499e58441671de authored by Rene Brun on 09 October 2006, 06:31:09 UTC, committed by Rene Brun on 09 October 2006, 06:31:09 UTC 
From Lorenzo:
 
ixes in GetStats() for taking into account underflow/overflow when TH1::StatOverflows is set and the modifications in TH2::ProjectionX and TH2::ProjectionY to use TH1::SetBinContent
instead of TH1::Fill in oder to have correct statistics in the projected histogram in case of weights. This fixes the bug 19628.
The number of entries in the projected histogram is set now to the number of effective entries.


git-svn-id: http://root.cern.ch/svn/root/trunk@16477 27541ba8-7e3a-0410-8455-c3a389f83636
1 parent 73d8d11
Raw File
hsum.py 
#
# To see the output of this macro, click begin_html <a href="gif/hsum.gif" >here</a> end_html
#    Simple example illustrating how to use the C++ interpreter	
#    to fill histograms in a loop and show the graphics results
#

from ROOT import TCanvas, TH1F, TSlider
from ROOT import gROOT, gBenchmark, gRandom


gROOT.Reset();

# Create a new canvas, and customize it.
c1 = TCanvas( 'c1', 'The HSUM example', 200, 10, 600, 400 )
c1.SetGrid();

gBenchmark.Start( 'hsum' )

# Create some histograms.
total  = TH1F( 'total', 'This is the total distribution', 100, -4, 4 )
main   = TH1F( 'main', 'Main contributor', 100, -4, 4 )
s1     = TH1F( 's1', 'This is the first signal', 100, -4, 4 )
s2     = TH1F( 's2', 'This is the second signal', 100, -4, 4 )
total.Sumw2()   # this makes sure that the sum of squares of weights will be stored

# Set canvas/frame attributes.
total.SetMarkerStyle( 21 )
total.SetMarkerSize( 0.7 )
main.SetFillColor( 16 )
s1.SetFillColor( 42 )
s2.SetFillColor( 46 )

# Initialize random number generator.
gRandom.SetSeed()
gauss, landau = gRandom.Gaus, gRandom.Landau

# for speed, bind and cache the Fill member functions
histos = [ 'total', 'main', 's1', 's2' ]
for name in histos:
   exec '%sFill = %s.Fill' % (name,name)

# Fill histograms randomly
kUPDATE = 500
for i in xrange( 10000 ):
 # Generate random values.
   xmain = gauss( -1, 1.5 )
   xs1   = gauss( -0.5, 0.5 )
   xs2   = landau( 1, 0.15 )
   mainFill( xmain )

 # Fill histograms.
   s1Fill( xs1, 0.3 )
   s2Fill( xs2, 0.2 )
   totalFill( xmain )
   totalFill( xs1, 0.3 )
   totalFill( xs2, 0.2 )

 # Update display every kUPDATE events.
   if i and (i%kUPDATE) == 0 :
      if i == kUPDATE :
         total.Draw( 'e1p' )
         main.Draw( 'same' )
         s1.Draw( 'same' )
         s2.Draw( 'same' )
         c1.Update()
         slider = TSlider( 'slider', 'test', 4.2, 0, 4.6, total.GetMaximum(), 38 )
         slider.SetFillColor( 46 )

      if slider:
         slider.SetRange( 0, float(i) / 10000. )

      c1.Modified()
      c1.Update()

# Destroy member functions cache.
for name in histos:
   exec 'del %sFill' % name
del histos

# Done, finalized and trigger an update.
slider.SetRange( 0, 1 )
total.Draw( 'sameaxis' ) # to redraw axis hidden by the fill area
c1.Modified()
c1.Update()

gBenchmark.Show( 'hsum' )
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