Hi,
That sounds like it might be quite useful. What I'm doing is generating
some predicates that involve addition/subtraction/comparison of integers
and concatenation/comparison of lists of some abstract thing, and then
trying to simplify them. An example would be simplifying
\exists p_before . \exists p_after . \exists q_before . \exists q_after .
\exists as . \exists bs . \exists cs . (length p_before == p_pos && length
q_before == q_pos && (p_before == as && q_after == cs) && p_before ++
p_new ++ p_after == as ++ p_new ++ bs ++ q_old ++ cs && as ++ p_new ++ bs
++ q_old ++ cs == q_before ++ q_old ++ q_after)
into
q_pos - (p_pos + length p_new) >= 0
which uses some properties of length as well as some arithmetic. I don't
expect this all to be done magically for me, but I'd like as much help as
possible - at the moment I've been growing my own library of predicate
transformations but it's all a bit ad-hoc.
If I could look at your code I'd be very interested.
Cheers,
Ganesh
On Thu, 4 Dec 2008, Immanuel Normann wrote:
Hi Ganesh,
manipulating predicate formulae was a central part of my PhD research. I
implemented some normalization and standarcization functions in Haskell -
inspired by term rewriting (like normalization to Boolean ring
representation) as well as (as far as I know) novell ideas (standardization
of quantified formulae w.r.t associativity and commutativity).
If you are interested in that stuff I am pleased to provide you with more
information. May be you can describe in more detail what you are looking
for.
Best,
Immanuel
2008/11/30 Ganesh Sittampalam <[EMAIL PROTECTED]>
Hi,
Are there any Haskell libraries around for manipulating predicate formulae?
I had a look on hackage but couldn't spot anything.
I am generating complex expressions that I'd like some programmatic help in
simplifying.
Cheers,
Ganesh
_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
