This icon allows specifying any operation on an arbitrary number of input data icons, returning the result of the operation for visualising, saving or examining. Unlike its related icon Simple Formula this one is not limited in the operations it can perform.
This icon cannot be called from Macro/Python - however these computations can easily be implemented in both languages.
The Formula Editor
The Formula icon editor only contains atext editor where the code to be executed can be specified. The syntax for the operators is the same as that for the Macro language but with the following restrictions :
There is no assignment of the result to a variable, i.e. enter
z500 / 9.8
not
h = z500 / 9.8
- Macro-style comments (anything preceded by #) are not allowed
- The formula must be specified in a single line of code, but you can use a Formula icon as input to another Formula icon
The input data must reside inside the Metview environment - all paths you specify are relative to the Metview root directory, e.g.
/mydata/T2 - 273.16
where the initial "/" stands for $HOME/metview.
Provided these restrictions are obeyed, all macro functions and operations can be used in this icon. Obviously, variable names used in the expressions must correspond to existing icons in the Metview environment.