Re: ...Contemplating unspecified constraint SOLVERS.

On Fri, 26 Aug 2005 22:29:40 -0400, "Dirk Mittler"
<mdirk@xxxxxxxxxxxx> wrote:

>
>"A.L." <alewando_won_@xxxxxxxxxxxxxxx> wrote in message
>news:9v7pg1pr95s0q0dh6nl95fpqm70ra2fkpb@xxxxxxxxxx
>
>>
>> Could you please summarize in one SHORT paragraph what is your
>> point?...
>>
>> A.L.
>
>You are focussing on the fact that an earlier exercise of mine, which people
>would have a hard time even to find on the bulletin board by now, was in
>fact not functional, and that yet I spent time on it. But I believe that one
>would need to understand precisely the text which you have omitted here, in
>order to begin to write one's own constraint *solvers* . As opposed to just
>using a CLP(R) solving system that came with the Prolog compiler.

It is not one paragraph, and this is not short. In addition, despite
reading your post multiple times, I have no idea what is your point.

As I understand (and I may be wrong...) one is that Bratko doesn't
explain how to write your own constraint solver. This is not a
rocket science to write simple (probably not efficient) constraint
solver. Taka a book about constraint programming (Krzysztof Apt
dicusses this in his book in details, although the code he provides
is not in Prolog) or implement Prolog constraint solver that is
posted on Roman Bartak's page:

http://kti.ms.mff.cuni.cz/~bartak/html/constraints.html

See the section

"CSP (Constraint Satisfaction Problems) (1996)

The program implements a skeleton for labeling, the main part of CSP
solvers. You need to include a plug-in module containing a
constraint solver to get a specific labeling procedure. Two examples
of plug-in modules are enclosed.

PROLOG source code of labeling kernel
plug-in module for constraints over integers (backtracking)
plug-in module for constraints over integers (forward checking)
Word Puzzle Solver

This is a program, based on CSP, for solving word puzzles. Example
of usage is enclosed.

PROLOG source code of Word Puzzle Solver
word puzzle example.."

In addition, there are a lot of publications about implementing
constraint solvers in Prolog or extending Prolog for constraint
solving. See papers by Daniel Diaz who did this for Gnu Prolog. Go
to SICS page and look for SICStus Prolog. There are publications by
Mats Carlsson who implemented constraint solver for SICStus Prolog.

Use google. Stop complaining.

A.L.
.

Relevant Pages

  • Re: ...Contemplating unspecified constraint SOLVERS.
    ... >>using a CLPsolving system that came with the Prolog compiler. ... > explain how to write your own constraint solver. ... > PROLOG source code of Word Puzzle Solver ...
    (comp.lang.prolog)
  • Re: ...Constraints and attributes.
    ... I possess SWI-Prolog with CLPand have now looked at some examples ... observation is that I can understand the constraint solver which is given as ... >>using a CLPsolving system that came with the Prolog compiler. ... > PROLOG source code of Word Puzzle Solver ...
    (comp.lang.prolog)
  • Re: Car-sequencing problem
    ... >I'm trying to learn Prolog because I must develop an application for ... In particular I must plan a solver in order to resolve the ... implement constraint solver in standard Prolog see Roman Bartak's ... PROLOG source code of Word Puzzle Solver ...
    (comp.lang.prolog)
  • Re: Car-sequencing problem
    ... >>I'm trying to learn Prolog because I must develop an application for ... In particular I must plan a solver in order to resolve the ... > implement constraint solver in standard Prolog see Roman Bartak's ... > PROLOG source code of Word Puzzle Solver ...
    (comp.lang.prolog)
  • Re: ...Contemplating unspecified constraint SOLVERS.
    ... using a CLPsolving system that came with the Prolog compiler. ... And Ivan Bratko's book nowhere explains how to write your own constraint ... write a constraint solver requires that one understands the CHR, ... I've actually been programming for 30 years or so, ...
    (comp.lang.prolog)