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rf407_latextables.py
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1 ## \file
2 ## \ingroup tutorial_roofit
3 ## \notebook -nodraw
4 ##
5 ## Data and categories: latex printing of lists and sets of RooArgSets
6 ##
7 ## \macro_code
8 ##
9 ## \date February 2018
10 ## \authors Clemens Lange, Wouter Verkerke (C++ version)
11 
12 import ROOT
13 
14 
15 # Setup composite pdf
16 # --------------------------------------
17 
18 # Declare observable x
19 x = ROOT.RooRealVar("x", "x", 0, 10)
20 
21 # Create two Gaussian PDFs g1(x,mean1,sigma) anf g2(x,mean2,sigma) and
22 # their parameters
23 mean = ROOT.RooRealVar("mean", "mean of gaussians", 5)
24 sigma1 = ROOT.RooRealVar("sigma1", "width of gaussians", 0.5)
25 sigma2 = ROOT.RooRealVar("sigma2", "width of gaussians", 1)
26 sig1 = ROOT.RooGaussian("sig1", "Signal component 1", x, mean, sigma1)
27 sig2 = ROOT.RooGaussian("sig2", "Signal component 2", x, mean, sigma2)
28 
29 # Sum the signal components into a composite signal p.d.f.
30 sig1frac = ROOT.RooRealVar(
31  "sig1frac", "fraction of component 1 in signal", 0.8, 0., 1.)
32 sig = ROOT.RooAddPdf(
33  "sig", "Signal", ROOT.RooArgList(sig1, sig2), ROOT.RooArgList(sig1frac))
34 
35 # Build Chebychev polynomial p.d.f.
36 a0 = ROOT.RooRealVar("a0", "a0", 0.5, 0., 1.)
37 a1 = ROOT.RooRealVar("a1", "a1", -0.2, 0., 1.)
38 bkg1 = ROOT.RooChebychev("bkg1", "Background 1",
39  x, ROOT.RooArgList(a0, a1))
40 
41 # Build expontential pdf
42 alpha = ROOT.RooRealVar("alpha", "alpha", -1)
43 bkg2 = ROOT.RooExponential("bkg2", "Background 2", x, alpha)
44 
45 # Sum the background components into a composite background p.d.f.
46 bkg1frac = ROOT.RooRealVar(
47  "sig1frac", "fraction of component 1 in background", 0.2, 0., 1.)
48 bkg = ROOT.RooAddPdf(
49  "bkg", "Signal", ROOT.RooArgList(bkg1, bkg2), ROOT.RooArgList(sig1frac))
50 
51 # Sum the composite signal and background
52 bkgfrac = ROOT.RooRealVar("bkgfrac", "fraction of background", 0.5, 0., 1.)
53 model = ROOT.RooAddPdf(
54  "model", "g1+g2+a", ROOT.RooArgList(bkg, sig), ROOT.RooArgList(bkgfrac))
55 
56 # Make list of parameters before and after fit
57 # ----------------------------------------------------------------------------------------
58 
59 # Make list of model parameters
60 params = model.getParameters(ROOT.RooArgSet(x))
61 
62 # Save snapshot of prefit parameters
63 initParams = params.snapshot()
64 
65 # Do fit to data, obtain error estimates on parameters
66 data = model.generate(ROOT.RooArgSet(x), 1000)
67 model.fitTo(data)
68 
69 # Print LateX table of parameters of pdf
70 # --------------------------------------------------------------------------
71 
72 # Print parameter list in LaTeX for (one column with names, column with
73 # values)
74 params.printLatex()
75 
76 # Print parameter list in LaTeX for (names values|names values)
77 params.printLatex(ROOT.RooFit.Columns(2))
78 
79 # Print two parameter lists side by side (name values initvalues)
80 params.printLatex(ROOT.RooFit.Sibling(initParams))
81 
82 # Print two parameter lists side by side (name values initvalues|name
83 # values initvalues)
84 params.printLatex(ROOT.RooFit.Sibling(initParams), ROOT.RooFit.Columns(2))
85 
86 # Write LaTex table to file
87 params.printLatex(ROOT.RooFit.Sibling(initParams),
88  ROOT.RooFit.OutputFile("rf407_latextables.tex"))