rf503_wspaceread.py File Reference

Detailed Description

'ORGANIZATION AND SIMULTANEOUS FITS' RooFit tutorial macro #503

Reading and using a workspace

The input file for self macro is generated by rf502_wspaceread.py

 
import ROOT
 
 
# Read workspace from file
# -----------------------------------------------
 
# Open input file with workspace (generated by rf503_wspacewrite)
f = ROOT.TFile("rf502_workspace_py.root")
 
# Retrieve workspace from file
w = f.Get("w")
 
# Retrieve pdf, data from workspace
# -----------------------------------------------------------------
 
# Retrieve x, and data from workspace
x = w["x"]
model = w["model"]
data = w["modelData"]
 
# Print structure of composite p.d.f.
model.Print("t")
 
# Fit model to data, plot model
# ---------------------------------------------------------
 
# Fit model to data
model.fitTo(data, PrintLevel=-1)
 
# Plot data and PDF overlaid
xframe = x.frame(Title="Model and data read from workspace")
data.plotOn(xframe)
model.plotOn(xframe)
 
# Overlay the background component of model with a dashed line
model.plotOn(xframe, Components="bkg", LineStyle="--")
 
# Overlay the background+sig2 components of model with a dotted line
model.plotOn(xframe, Components="bkg,sig2", LineStyle=":")
 
# Draw the frame on the canvas
c = ROOT.TCanvas("rf503_wspaceread", "rf503_wspaceread", 600, 600)
ROOT.gPad.SetLeftMargin(0.15)
xframe.GetYaxis().SetTitleOffset(1.4)
xframe.Draw()
 
c.SaveAs("rf503_wspaceread.png")

0x565347e5bfb0 RooAddPdf::model = 1/1 [Auto,Clean] 
  0x56534aa595e0/V- RooChebychev::bkg = 1 [Auto,Dirty] 
    0x56534a305380/V- RooRealVar::x = 5
    0x565343e81e80/V- RooRealVar::a0 = 0.5
    0x565343e7a6c0/V- RooRealVar::a1 = 0
  0x56534aaf5c90/V- RooRealVar::bkgfrac = 0.5
  0x56534aae8b40/V- RooAddPdf::sig = 1/1 [Auto,Clean] 
    0x56534aa6f2d0/V- RooGaussian::sig1 = 1 [Auto,Dirty] 
      0x56534a305380/V- RooRealVar::x = 5
      0x56534974ccb0/V- RooRealVar::mean = 5
      0x565343e800a0/V- RooRealVar::sigma1 = 0.5
    0x565343e7c590/V- RooRealVar::sig1frac = 0.8
    0x56534aa7ca20/V- RooGaussian::sig2 = 1 [Auto,Dirty] 
      0x56534a305380/V- RooRealVar::x = 5
      0x56534974ccb0/V- RooRealVar::mean = 5
      0x56534a16c3a0/V- RooRealVar::sigma2 = 1
[#1] INFO:Fitting -- RooAbsPdf::fitTo(model) fixing normalization set for coefficient determination to observables in data
[#1] INFO:Fitting -- using generic CPU library compiled with no vectorizations
[#1] INFO:Fitting -- Creation of NLL object took 7.80984 ms
[#1] INFO:Fitting -- RooAddition::defaultErrorLevel(nll_model_modelData) Summation contains a RooNLLVar, using its error level
[#1] INFO:Minimization -- [fitFCN] No discrete parameters, performing continuous minimization only
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (bkg)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: ()
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (bkg,sig2)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: (sig)

Date

February 2018

Authors

Clemens Lange, Wouter Verkerke (C version)

Definition in file rf503_wspaceread.py.