[PYTHON MATRIX-SIG] Fast evaluation of numerical expressions

Hinsen Konrad hinsenk@ere.umontreal.ca
Sat, 13 Jan 1996 09:32:56 -0500

   This sounds like a useful idea.  Please proceed.

As soon as I find some spare time...

   (I particularly like the idea of using a 'variable' data type which
   can be subjected to normal operations, yielding a data structure
   representing the expression structure.  This could be used in a
   symbolic algebra package, as well...)

Indeed. Symbolic algebra in Python would be neat...

A nice feature of this approach is that existing code can be compiled
without modification. Any Python function foo(x) that consists of a
linear sequence of statements (no conditionals, no loops) can be
compiled as simply as

   compiled_foo = foo(variable(types.FloatType))

The tricky part will be the optimizer. I'd like to have at least
extraction of common subexpressions, which occur rather often
in numerical expressions.

Konrad Hinsen                     | E-Mail: hinsenk@ere.umontreal.ca
Departement de chimie             | Tel.: +1-514-343-6111 ext. 3953
Universite de Montreal            | Fax:  +1-514-343-7586
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