Thank you, it worked well. I can't find how in sympy i can obtain the
entire expression parsing tree. I want to be able to navigate from my
app, selecting part of the expression (having the expression tree and
navigation functions, this would be very easy), and applying to this
expression some
You might look at the preorder_traversal() and postorder_traversal() functions
in sympy/utilities/iterables.py:
In [4]: a = (x + 2)*(x + 1)**2
In [5]: from sympy.utilities.iterables import preorder_traversal,
postorder_traversal
In [6]: preorder_traversal(a)
Out[6]: generator object
