Dear all,
i’m facing a very basic issue.
I have TH2F plot where i need to put a measurement and display the correlation among the two variables
with an ellipse. How can i set the two radius of the ellipse so that they have the right dimension compared to x-y axes? I guess i need some conversion to pad coordinate system…thanks in advance for any help!
best,
Max
see example below
Rene
void circle() {
//a canvas with a fix aspect ratio
TCanvas *c1 = new TCanvas("c1");
Double_t w = gPad->GetWw()*gPad->GetAbsWNDC();
Double_t h = gPad->GetWh()*gPad->GetAbsHNDC();
Double_t xmin = 0;
Double_t xmax = 100;
Double_t ymin = 0;
Double_t ymax = xmax*h/w;
c1->SetFixedAspectRatio();
c1->Range(xmin,ymin,xmax,ymax);
TArc *arc = new TArc(50,50,10);
arc->Draw();
}