Hi Thijs
Sometime ago I downloaded the following from the knowledgebase so make no claims for it:
To print only a graph from the front panel, create a subVI with a graph on its front panel
Change the graph from an indicator to a control
Open the subVI and select Operate>>Print at Completion
Assign the subVI a connector and pass the data from the graph on the main VI to the graph on the subVI
It certainly worked OK for me so hope it's of help
Regards
Keith
