You can have multiple AND statements, but if there is an error in one of the expressions, or incompatible grids, it can be hard to know where that is happening.
What I would do to track down what's going wrong is to use Ferret to plot or list parts of your _expression_.
(I don't know what the grids are. Set the region specifiers so you can do useful 2D plots)
shade/k=1 ifv (temp_out ge 6 and temp_out le 20 ) then 1
or define variables similar to what you're going to compute and look at them
let temp_var = ifv (temp_out ge 6 and temp_out le 20 ) then 1
Once you know what's going on with your individual expressions, you could start putting them together, building towards the full _expression_ and again evaluate. So, can you do the calculation with temp and salt?
let u_acas_out = if (temp_out ge 6 and temp_out le 20 and salt_out ge 34.6 and salt_out le 36 ) then u_out
If that is successful, add more terms and work along. If you run into problems or see error messages, you've got a smaller set of things going on so you may be able to see where that's happening.
Also, if you write back, please say what error messages or other behavior you are seeing.
On 3/9/2015 6:54 AM, Lívia Sancho wrote: