Some frequent operations, even though surely covered somewhere in the manual or in the tutorials:

How To ...

Q: ... specify the axis range in numbers?
A: Ctrl+V opens the View window, in the Tab 2D view the input field Window contains the space-separated x_min x_max y_min y_max.
Q: ... combine (add, subtract, ...) fields?
A: Ctrl+Shift+E opens the Expressions Window. You can create a new expression and select the type on the right hand side (e.g. scalar or vector) and insert functions or variables from your current database to apply mathematical operations on them and combine them. After saving the expression by clicking apply, you can add them like any other data field.
Q: ... combine fields from different time snapshots or databases?
A: Open the Data Level Comparison Wizard with Ctrl+Shift+D. It will guide you through the process of creating a new expression with the field that you want to compare with.
Q: ... change the language of the GUI?
A: That cannot be done via the GUI itself. The Linux version can be launched as visit -lang en from the command line. In the Windows version, the option -lang has no effect; hence, a hack has to be used.

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