[ncl-talk] dummy wks for get_isollines()- best/better practice?

[Alan Brammer]

Hi all, 

I’m writing a function that utilises the get_isollines function.  I don’t want a plot however, so am currently generating a png workstation then creating a plot but never drawing or framing.  This works fine and seems to be fast enough for now, just wondering if there is a cleaner way?  

 Am I unnecessarily creating a hidden png somewhere on my filesystem or does that not happen until draw and frame are called? 
If there are system calls occurring in the background is there any difference (in terms of computation time) about the type of “fake” workstation I create? 
 Is it possible to use get_isollines without the dummy wks and plot calls .e.g Is there a background marching squares algorithm already setup for wrapping into NCL?

Thanks, 

Alan.