[ferret_users] getting dimension in a user variable

[DELCLAUX Francois <delclaux@xxxxxxxxxxxxxxxxxxx>]

Hi,

I would like to define a variable containing the dimension of a file 
variable, ie :
suppose precipitation "prj"  is a 1D variable for which i varies from 1 
to 10.
Then I would like to define a variable ,  nx, such that nx = 10 .
yes?  let nx = ???

What's the best way for doing that ?

Sincerely

François Delclaux