rf407_latextables.py

#####################################
#
# 'DATA AND CATEGORIES' ROOT.RooFit tutorial macro #407
#
# Latex printing of lists and sets of ROOT.RooArgSets
#
#
#
# 07/2008 - Wouter Verkerke
#
# /


import ROOT


def rf407_latextables():
    # S e t u p   c o m p o s i t e    p d f
    # --------------------------------------

    # Declare observable x
    x = ROOT.RooRealVar("x", "x", 0, 10)

    # Create two Gaussian PDFs g1(x,mean1,sigma) anf g2(x,mean2,sigma) and
    # their parameters
    mean = ROOT.RooRealVar("mean", "mean of gaussians", 5)
    sigma1 = ROOT.RooRealVar("sigma1", "width of gaussians", 0.5)
    sigma2 = ROOT.RooRealVar("sigma2", "width of gaussians", 1)
    sig1 = ROOT.RooGaussian("sig1", "Signal component 1", x, mean, sigma1)
    sig2 = ROOT.RooGaussian("sig2", "Signal component 2", x, mean, sigma2)

    # Sum the signal components into a composite signal p.d.f.
    sig1frac = ROOT.RooRealVar(
        "sig1frac", "fraction of component 1 in signal", 0.8, 0., 1.)
    sig = ROOT.RooAddPdf(
        "sig", "Signal", ROOT.RooArgList(sig1, sig2), ROOT.RooArgList(sig1frac))

    # Build Chebychev polynomial p.d.f.
    a0 = ROOT.RooRealVar("a0", "a0", 0.5, 0., 1.)
    a1 = ROOT.RooRealVar("a1", "a1", -0.2, 0., 1.)
    bkg1 = ROOT.RooChebychev("bkg1", "Background 1",
                             x, ROOT.RooArgList(a0, a1))

    # Build expontential pdf
    alpha = ROOT.RooRealVar("alpha", "alpha", -1)
    bkg2 = ROOT.RooExponential("bkg2", "Background 2", x, alpha)

    # Sum the background components into a composite background p.d.f.
    bkg1frac = ROOT.RooRealVar(
        "sig1frac", "fraction of component 1 in background", 0.2, 0., 1.)
    bkg = ROOT.RooAddPdf(
        "bkg", "Signal", ROOT.RooArgList(bkg1, bkg2), ROOT.RooArgList(sig1frac))

    # Sum the composite signal and background
    bkgfrac = ROOT.RooRealVar("bkgfrac", "fraction of background", 0.5, 0., 1.)
    model = ROOT.RooAddPdf(
        "model", "g1+g2+a", ROOT.RooArgList(bkg, sig), ROOT.RooArgList(bkgfrac))

    # M a k e   l i s t   o f   p a r a m e t e r s   b e f o r e   a n d   a f t e r   f i t
    # ----------------------------------------------------------------------------------------

    # Make list of model parameters
    params = model.getParameters(ROOT.RooArgSet(x))

    # Save snapshot of prefit parameters
    initParams = params.snapshot()

    # Do fit to data, obtain error estimates on parameters
    data = model.generate(ROOT.RooArgSet(x), 1000)
    model.fitTo(data)

    # P r i n t   l a t ex   t a b l e   o f   p a r a m e t e r s   o f   p d f
    # --------------------------------------------------------------------------

    # Print parameter list in LaTeX for (one column with names, column with
    # values)
    params.printLatex()

    # Print parameter list in LaTeX for (names values|names values)
    params.printLatex(ROOT.RooFit.Columns(2))

    # Print two parameter lists side by side (name values initvalues)
    params.printLatex(ROOT.RooFit.Sibling(initParams))

    # Print two parameter lists side by side (name values initvalues|name
    # values initvalues)
    params.printLatex(ROOT.RooFit.Sibling(initParams), ROOT.RooFit.Columns(2))

    # Write LaTex table to file
    params.printLatex(ROOT.RooFit.Sibling(initParams),
                      ROOT.RooFit.OutputFile("rf407_latextables.tex"))


if __name__ == "__main__":
    rf407_latextables()