make two windows activated at the same time

[grastro]

Hi guys
I want to produce new expressions in VisiIt. I need to combine two variables from two different files. Whatever the files' format is, it gives an error while plotting the new expression complaining that one of the variables is not valid. Since the variable whose window is not active is invalid, I think i may need to make both of them activated at the same time, but i can't, although both files with those essential variables are open with existing plots. How I can activate both simultaneously? I should add overlying does not work, too (making the same error: invalid variable). Thanks in advance.

[brugger1]

Hi,

To combine the variables from 2 databases into a single expression you need to use the "Cross Mesh Field Expressions". The are used to map a variable from one mesh onto another mesh so that they are both defined on the same mesh and can then be combined in an expression. They are documented here:

Database comparison

Comparison expressions

[grastro]

Thank you very much. I'm trying to make it work for my sets of data which are of different formats. I hope it goes well. Again thanks a lot :)

[markcmiller86]

yes, that should work ok too. Once it gets read into VisIt from any reader, then the expression system can work on it as @brugger1 mentions above.

[grastro]

Yes, it worked!