Next question to TF1

ROOT
1

This code works:

TF1 *f1 = new TF1(“myfunc”,“TMath::Gaus(x,0,2)”,-5,5);

f1->Draw();

TF1 *f1t = new TF1(“myfunc”,“TMath::Gaus(x,0,5)”,-5,5);

f1t->Draw(“SAME”);

BUT this code doesn’t :

TF1 *f1 = new TF1(“myfunc”,Gfunction1,-5,5,2);
f1->SetParameters(2,0);

f1->Draw();

TF1 *f2 = new TF1(“myfunc”,Gfunction2,-5,5,2);
f2->SetParameters(5,0);

f2->Draw(“SAME”);

with some functions like these:

Double_t Gfunction1(Double_t *x, Double_t *para)
{
Double_t x1 =x[0];

Double_t gf1 = 1/(TMath::Sqrt(2TMath::Pi())para[0]) * TMath::Exp(-0.5((x1-para[1])/para[0])((x1-para[1])/para[0]));

return gf1;
}

Double_t Gfunction2(Double_t *x, Double_t *parb)
{
Double_t x2 =x[0];

Double_t gf2 = 1/(TMath::Sqrt(2TMath::Pi())parb[0]) * TMath::Exp(-0.5((x2-parb[1])/parb[0])((x2-parb[1])/parb[0]));

return gf2;
}

This really drives me nuts !! Please help !

2

You should not give the same name to two different functions.
Replace
TF1 *f2 = new TF1(“myfunc”,Gfunction2,-5,5,2);
by
TF1 *f2 = new TF1(“myfunc2”,Gfunction2,-5,5,2);

Rene

3

Hm…‘cough’ i should have seen this. Thank you Rene !