Re: expression tree?

[Richard Morris]

Farida,

It is a tricky problem. It would be very difficult to solve it by changing the parsing stage. A better approach is to modify the parse tree after parsing. As a first step you can use the com.singularsys.jep.walkers.ExpressionConsolidator this can compress nested additions (or multiplications) into a single nary operator giving something like

                         +   

       *          *             *            *

   A    B   C    D     A    D     B    C

you could then walk the tree again and split the nary operators as desired.

Richard

On Sunday, June 2, 2013 11:56:24 AM UTC+1, Farida Sabry wrote:

I am new to JEP, I am trying to use it to get the expression tree to be used in another task rather than evaluation.

But I found that using:  

String expression = "A*B+C*D+A*D+B*C";

Node tree = jep.parse(expression); 

results in a tree constructed  in a way different than that I need.

The tree produced is having the structure:

                             +

                   +                 *

            +             *       B   C

       *          *    A    D

   A    B   C    D

while I want it to be:

                         +   

            +                         +

       *          *             *            *

   A    B   C    D     A    D     B    C

Is there a way in JEP to parse the expression in that way?

Or do I have to overload a parse function to do that?

Thanks for the good work done in JEP. 

Best regards,

Farida