Other considerations: is SymPy able to match subtrees in the args tree? What I have understood from the docstrings, is that the matcher tries to match the whole expression tree, not a part of it.
The tensor module is somewhat anomalous, because the way you write tensors is not the same as the expression tree, which contains additional information. I should be interesting to have a look at xAct into detail, I suppose they use something similar to assumptions or tools by Mathematica. I have not a very good knowledge of Mathematica language, though. In any case, subtree pattern matching could be an interesting matter, that's more graph-like than tree-like. I'm still convinced that the tensor module needs its own pattern matcher, the other way would be to relocate arg-tree internal data to the assumptions, or to some other global variable. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy. For more options, visit https://groups.google.com/groups/opt_out.
