Re: Usage of FomulaManager

Hi Mathias,

I will second Bill's statement that you should look into Jython for
your needs, as it is a more flexible and complete system for doing
the kinds of things you are attempting.

However, since I did write the visad.formula stuff, I thought I'd
answer your questions too. :-)

>Is there a way to construct a FormulaManager that is able to parse all
>these expressions or do I have to do some kind of pre-parsing which
>filters everything the FormulaManager is not able to parse.

If you wanted to use FormulaManager, you'd have to design wrappers for
all object types that are not visad.Things, to make them into Things.
The classes visad.formula.VMethod and visad.formula.VRealType do this
for java.lang.reflect.Method and visad.RealType, respectively.

In your case, I suspect it would be quite a pain, and that Jython
would work much more elegantly for you.

>Is there a way to get Exceptions or "error reports" from the
>FormulaManager if it was not able to parse the line?

FormulaManager.getErrors() returns an array of String error messages.
This method is what the SpreadSheet uses to obtain the formula errors
displayed inside the SpreadSheet cells when something goes wrong.

>Is there a general documentation of the visad.formula package? I only
>found the docs and examples included in the visad.ss package and its
>documentation.

Documentation for the visad.formula package is available as part
of the VisAD Javadocs at:
    http://www.ssec.wisc.edu/~dglo/docs/index.html

-Curtis