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The ASP solving process via Graph coloring

This little (and very first!) tutorial explains the underlying workflow in Answer Set Programming (ASP) . For illustration, we use graph coloring as a guiding example. The first part explains the basic modeling methodology of ASP, while the second one is dedicated to handling ASP systems. On the side, basic statistics are used to gain insights into the ASP solving process, and finally the relation among the ASP systems clasp, gringo, and clingo is briefly discussed.

Video (part one 10:34, part two 16:44), Script (org, html, tex, pdf, txt), Files (tgz, zip)

Basic modeling in ASP via n-Queens puzzles

This second (and yet clumsy!) tutorial deals with basic modeling techniques in Answer Set Programming (ASP). We illustrate these techniques by modeling the n-Queens puzzle in various ways. The first part discusses a basic encoding along with some arising pitfalls. The add-on to part one motivates the choice of this encoding. The second part provides a more advanced encoding illustrating the advantage of using cardinality constraints; it discusses their impact on grounding and searching (by inspecting clasp's statistics). The first add-on gives an even more compact encoding (also by Roland Kaminski) and the second one discusses clasp's treatment of cardinality constraints. The third part talks about issues with declarativity and scalability. The fourth part presents a further improved encoding, obtained by replacing a source of combinatorial search within grounding by pre-computation. The fifth part explores a new experimental feature of gringo that allows for expressing finite linear constraint satisfaction problems within its modeling language and for passing them on to off-the-shelf ASP solvers. The sixth and final part wraps up the tutorial by applying the most promising encodings to more demanding problems, namely the 1000-Queens puzzle.

Video (part one 11:39; one+ 2:59, part two 8:59; two+ 3:06; two++ 4:02, part three 4:51, part four 8:35, part five 11:35, part six 4:38), Script (org, html, tex, pdf, txt), Files (tgz, zip)

Optimization in clasp 3 via traveling salespersons

This video provides an introduction to optimization in ASP while focusing on the capacities of the clasp 3 series. The first part sets the stage by describing a well-known ASP encoding of the traveling salesperson problem. The second part introduces clasp's two basic approaches to optimization, viz. the branch-and-bound and unsatisfiable-core-based approach, and it discusses the different phases of optimization processes, namely convergence and optimality. Part three introduces a quite effective design pattern for modeling optimization problems (thanks to Martin Gebser). Part four is dedicated to clasp's manifold heuristics and strategies related to optimization: (A) --progress-saving, (B) --opt-strategy and there are more to come :)

Video (part one 12:01, part two 8:21, part three 14:16, part four 3:58: A 6:28, B 22:29), Script (org, html, tex, pdf, txt), Files (tgz, zip)

Ricochet Robots with ASP

Video 13:34, Resources

Talks and Tutorials

Answer Set Solving in Practice (Tutorial)

AAAI'13, Seattle, USA, Video (part one 1:28:21, part two 1:59:22), Slides

Experiencing Answer Set Programming at Work, Today and Tomorrow

ICLP'13, Istanbul, Turkey, Video 1:01:42, Slides

Answer Set Programming: Boolean Constraint Solving for Knowledge Representation and Reasoning

CP'13, Uppsala, Sweden, Video 1:05:15, Slides

More teaching material can be found here.