Other vector formats (to be continued)

[Salvador Calabria Montero <scalabri@xxxxxxxxxxxxxx>]

Hello all, 

Thank you for former suggestions about how to do vector in other formats, but 
I keep searching to do the following:
I would like to do vectors 'with barbs' in the same way that GRADS do it with 
its command "display barb". That is, what I need is to draw vectors with a 
barb that shows the magnitude of the speed. I suspect that this is not 
possible with ferret, at least in an easy way.
If anybody could give me a hint, or tell me that I did not try to find the 
way because it is impossible, I would appreciate it.

Thank you for your help in advance