[PURRS-devel] Type gen

[Tatiana Zolo]

Hi,
my problem is the following and it can be split in 3 parts:
1) transform my object (expressions of various types) in a giac object
2) factorize the giac object
3) come back to my object.

I know how to do the problem 2): I used  the type `gen' and the
functions in the file
sym2poly.{h,cc}.

About the problems 1) and 2) I did something in both the directions but
I want ask you
the best method to decompose a type gen.
For example, if I have `g' of the type gen, where g = a + b + c + d,
how can I consider the single summands? The same problem with a product
of gen,
a power of gen, ...
How can I know if `g' is a sum of gen? Or a product of gen?
I did not find these methods in the file gen.h.
Is there documentation about these topics?

Thanks, bye
        Tatiana