doc/v624/rf504__simwstool_8py.html

import ROOT


# Create master pdf

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


# Construct gauss(x,m,s)

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

m = ROOT.RooRealVar("m", "m", 0, -10, 10)

s = ROOT.RooRealVar("s", "s", 1, -10, 10)

gauss = ROOT.RooGaussian("g", "g", x, m, s)


# Construct poly(x,p0)

p0 = ROOT.RooRealVar("p0", "p0", 0.01, 0., 1.)

poly = ROOT.RooPolynomial("p", "p", x, ROOT.RooArgList(p0))


# model = f*gauss(x) + (1-f)*poly(x)

f = ROOT.RooRealVar("f", "f", 0.5, 0., 1.)

model = ROOT.RooAddPdf("model", "model", ROOT.RooArgList(

    gauss, poly), ROOT.RooArgList(f))


# Create category observables for splitting

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


# Define two categories that can be used for splitting

c = ROOT.RooCategory("c", "c")

c.defineType("run1")

c.defineType("run2")


d = ROOT.RooCategory("d", "d")

d.defineType("foo")

d.defineType("bar")


# Set up SimWSTool

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


# Import ingredients in a workspace

w = ROOT.RooWorkspace("w", "w")

w.Import(ROOT.RooArgSet(model, c, d))


# Make Sim builder tool

sct = ROOT.RooSimWSTool(w)


# Build a simultaneous model with one split

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


# Construct a simultaneous pdf with the following form

#

# model_run1(x) = f*gauss_run1(x,m_run1,s) + (1-f)*poly

# model_run2(x) = f*gauss_run2(x,m_run2,s) + (1-f)*poly

# simpdf(x,c) = model_run1(x) if c=="run1"

#             = model_run2(x) if c=="run2"

#

# Returned pdf is owned by the workspace

model_sim = sct.build("model_sim", "model",

                      ROOT.RooFit.SplitParam("m", "c"))


# Print tree structure of model

model_sim.Print("t")


# Adjust model_sim parameters in workspace

w.var("m_run1").setVal(-3)

w.var("m_run2").setVal(+3)


# Print contents of workspace

w.Print("v")


# Build a simultaneous model with product split

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


# Build another simultaneous pdf using a composite split in states c X d

model_sim2 = sct.build("model_sim2", "model",

                       ROOT.RooFit.SplitParam("p0", "c,d"))


# Print tree structure of self model

model_sim2.Print("t")