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Hi I've some trivial question:

for exercise I want to parse a string that like this:

"x -34 + 65 * 96 = 102"

now if I had this ("(25+24)/2") is extremely easy to have a result but
I want to resolve the above string (for the 'x' variable) what can I
do?

Especially for symbolic function I think that I've to build an
'operations tree' with a variable table.
I want to know how Derive parse this kind of string.

If I've to build a tree, please give me resources and/or examples of
what physically is a tree and how to build on python.

Thanks

On Dec 18, 10:43 pm, Federico <federico.bertola....@gmail.com> wrote:
> Hi I've some trivial question:
>
> for exercise I want to parse a string that like this:
>
> "x -34 + 65 * 96 = 102"
>
> now if I had this ("(25+24)/2") is extremely easy to have a result but
> I want to resolve the above string (for the 'x' variable) what can I
> do?
>
> Especially for symbolic function I think that I've to build an
> 'operations tree' with a variable table.
> I want to know how Derive parse this kind of string.
>
> If I've to build a tree, please give me resources and/or examples of
> what physically is a tree and how to build on python.
>
> Thanks

You can use a parser generator to build the syntax tree that you want.
See http://wiki.python.org/moin/LanguageParsing for a list.

Perhaps pyparsing is a good one to start with?
http://pyparsing.wikispaces.com/

HTH

--
Arnaud