How i can plot result in my GUI ?

[21did21]

Plotting a point doesn't cause an immediate repaint of the user interface. Events need to be processed so that Qt can ask your widget to repaint itself. Without that your loop runs continously and you will only see the final result. Please read the docs or search the forum for event processing and redrawing issues, it's a frequent problem.

thank you for this answer, but sorry i don't understand that you speak about.

can you reformulate please because i am not an english people.

i have two difficulty:
=> Qwt and the english language

EDIT:
if i understand, you say:
=> my programm is good but Qt have not time to replot correctly, so i just can see the final result ?
=> have you link which speaks about this to understand how i can resolve my problem?