doc/v624/rf405__realtocatfuncs_8py.html

import ROOT


# Define pdf in x, sample dataset in x

# ------------------------------------------------------------------------


# Define a dummy PDF in x

x = ROOT.RooRealVar("x", "x", 0, 10)

a = ROOT.RooArgusBG("a", "argus(x)", x, ROOT.RooFit.RooConst(

    10), ROOT.RooFit.RooConst(-1))


# Generate a dummy dataset

data = a.generate(ROOT.RooArgSet(x), 10000)


# Create a threshold real -> cat function

# --------------------------------------------------------------------------


# A RooThresholdCategory is a category function that maps regions in a real-valued

# input observable observables to state names. At construction time a 'default'

# state name must be specified to which all values of x are mapped that are not

# otherwise assigned

xRegion = ROOT.RooThresholdCategory(

    "xRegion", "region of x", x, "Background")


# Specify thresholds and state assignments one-by-one.

# Each statement specifies that all values _below_ the given value

# (and above any lower specified threshold) are mapped to the

# category state with the given name

#

# Background | SideBand | Signal | SideBand | Background

#           4.23       5.23     8.23       9.23

xRegion.addThreshold(4.23, "Background")

xRegion.addThreshold(5.23, "SideBand")

xRegion.addThreshold(8.23, "Signal")

xRegion.addThreshold(9.23, "SideBand")


# Use threshold function to plot data regions

# ----------------------------------------------


# Add values of threshold function to dataset so that it can be used as

# observable

data.addColumn(xRegion)


# Make plot of data in x

xframe = x.frame(ROOT.RooFit.Title(

    "Demo of threshold and binning mapping functions"))

data.plotOn(xframe)


# Use calculated category to select sideband data

data.plotOn(

    xframe,

    ROOT.RooFit.Cut("xRegion==xRegion::SideBand"),

    ROOT.RooFit.MarkerColor(

        ROOT.kRed),

    ROOT.RooFit.LineColor(

        ROOT.kRed))


# Create a binning real -> cat function

# ----------------------------------------------------------------------


# A RooBinningCategory is a category function that maps bins of a (named) binning definition

# in a real-valued input observable observables to state names. The state names are automatically

# constructed from the variable name, binning name and the bin number. If no binning name

# is specified the default binning is mapped


x.setBins(10, "coarse")

xBins = ROOT.RooBinningCategory("xBins", "coarse bins in x", x, "coarse")


# Use binning function for tabulation and plotting

# -----------------------------------------------------------------------------------------------


# Print table of xBins state multiplicity. Note that xBins does not need to be an observable in data

# it can be a function of observables in data as well

xbtable = data.table(xBins)

xbtable.Print("v")


# Add values of xBins function to dataset so that it can be used as

# observable

xb = data.addColumn(xBins)


# Define range "alt" as including bins 1,3,5,7,9

xb.setRange(

    "alt",

    "x_coarse_bin1,x_coarse_bin3,x_coarse_bin5,x_coarse_bin7,x_coarse_bin9")


# Construct subset of data matching range "alt" but only for the first

# 5000 events and plot it on the frame

dataSel = data.reduce(ROOT.RooFit.CutRange(

    "alt"), ROOT.RooFit.EventRange(0, 5000))

dataSel.plotOn(xframe, ROOT.RooFit.MarkerColor(ROOT.kGreen),

               ROOT.RooFit.LineColor(ROOT.kGreen))


c = ROOT.TCanvas("rf405_realtocatfuncs", "rf405_realtocatfuncs", 600, 600)

xframe.SetMinimum(0.01)

ROOT.gPad.SetLeftMargin(0.15)

xframe.GetYaxis().SetTitleOffset(1.4)

xframe.Draw()


c.SaveAs("rf405_realtocatfuncs.png")