coordinate system

[Lesiok]

Maybe look at Qwt

[Wojtek.wk]

I fail to see what the problem is Maybe you could explain what you mean by "write a coordinate system"?

I want to have drawn something like this: http://upload.wikimedia.org/wikipedi...ate-system.svg

@Lesiok: Thank you, very interesting

[wysota]

I think we understand different things by the term "coordinate system" You mean you want to draw a graph/chart, right?

Is the problem mathematical or you don't know how to draw primitives or what exactly?

The image you link to is invalid, by the way... each axis should only have one arrow head :]

[TheJim01]

You could make your own custom widget for this. If so, you're going to want to read about QImage and QPainter.