[ROOT] TF2 user defined. Out of range???

From: jgonzalez@hepmail.physics.neu.edu
Date: Mon Aug 11 2003 - 21:18:14 MEST 

Hi all

I got the following problem with the script I attached in the end:

It works fine but when I place the cursor on top of the pad then a message
appears "Error: operator '/' divided by zero FILE:like.C LINE:10"

The weird thing is that 0 shouldn't be in the range for any parameter so
how come root is evaluating the function there?

In case you are interested:
root version 3.05/03

Thanks

Javier

P.s.: here goes the file (copy pasted)

Float_t loglike(Double_t* x, Double_t* par)
{
  Float_t loglikelihood = 0;
  Float_t level[5] = {0.7,0.8,0.9,1.0,1.2};
  Float_t time[5] = {38.36,41.63,45.33,49.97,55.39};

  if(x[1] == 0) cout << "x[1] is zero!!" << endl;
  for(int i = 0; i != 5; i++)
    {
      Float_t calcul = (0.3066/x[1] + 0.1749*(1-x[0])*(level[i]+0.2838) +
0.003522);
      loglikelihood += pow( (time[i] - calcul),2.0)/2;
    }
  return loglikelihood;
}

void like()
{
  // x_range is (0.8,0.98)  y_range is (1000.0,10000.0)

TF2* chi2 = new TF2("chi2",loglike,0.8,0.98,1000.0,10000.0,0);
TCanvas* micanvas = new TCanvas();
 chi2->Draw();


}

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