Display the vertex in RooEllipse

Newbie
1

Hi,

I’m trying to plot an ellipse using RooEllipse and I want the vertex to plotted as well:

RooEllipse *el = new RooEllipse("",0.0039,-0.0002,0.0033,0.0036,0.13,100);
el->Draw();

Is it possible to display the vertex of this ellipse? A marker at (0.0039,-0.0002)
Any help is highly appreciated.

Thanks,

Dennis

_ROOT Version: 6.20.06
_Platform: Ubuntu 18.04
_Compiler:

2

RooEllipse is a TGraph so the option “P” in te Draw directive will plot markers.

3

Thank you very much for your help @couet,

The markers are displayed now. But I want also to display the point at the center (0.0039,-0.0002) of the ellipse. This center marker is need because it is my reference for the uncertainty values. Is there a workaround on this?

Thanks again,

Dennis

4

The ellipse center is not part to the graph data points. To display it you will need to draw a TMarker at the center coordinates.

5

Many thanks for your help @couet. It works fine now.

Sincerely,

Dennis