Help: How to draw markers on plot?

[Uwe]

I asked this question before but did not get the answer so I try again. Could someone help me on how to draw simple marker on my plot at a given point x, y? Something like an "X" or "+"?

Surprisingly a marker is displayed by a class called QwtPlotMarker.
Did you ever look into the docs or the examples, that are included in the Qwt package ?

Uwe