Gecode version 3.0.1 and Gecode/FlatZinc 1.5 released
Version 3.0.1 of Gecode is relased. It contains mostly bug fixes:
This is a bug fix release fixing an embarassing bug in reified Boolean linear constraints.
- Finite domain integers
- Bug fixes
- IntSetArgs no longer inherit from PrimArgArray, which was wrong as IntSet is no primitive type and hence does not support vararg initializers. (minor)
- Fixed bug in reified Boolean linear constraints (an optimization is currently disabled and will be active in the next release: the optimization was incorrect and was never tested). (major, thanks to Alberto Delgado)
- Example scripts
- Additions
- Added new example for Radiotherapy. (minor)
- Bug fixes
- The examples now pass the c-d and a-d command line options correctly to Gist. (minor)
- The Steel Mill Slab Design example had two bugs in the search heuristic and a missing redundant constraint. (minor, bugzilla entry, thanks to Chris Mears)
Gecode/FlatZinc has been updated to version 1.5. The bug fix here is very interesting (and exiting) since Gist now also works with Gecode/FlatZinc.
Gist in Gecode and Gecode/FlatZinc
Gist for Gecode has been around for time, and was officially in the distribution in version 3.0.0. In Modeling with Gecode (PDF) there is a section how to program and use Gist.
Stable Marriage Problem.
As a first example of Gist with Gecode/FlatZinc (i.e. MiniZinc models): stable_marriage.pdf is a PDF file which shows the full search tree for the MiniZinc model stable_marriage.mzn. The green nodes are solutions, the blue nodes are choice points, the red squares are failures, and the big red triangles are a sub tree of failures.
Running the model with fz -mode stats stable_marriage.fzn gives the following result.
wife : [7, 5, 9, 8, 3, 6, 1, 4, 2]
husband: [7, 9, 5, 8, 2, 6, 1, 4, 3]
----------
wife : [6, 5, 9, 8, 3, 7, 1, 4, 2]
husband: [7, 9, 5, 8, 2, 1, 6, 4, 3]
----------
wife : [6, 4, 9, 8, 3, 7, 1, 5, 2]
husband: [7, 9, 5, 2, 8, 1, 6, 4, 3]
----------
wife : [6, 1, 4, 8, 5, 9, 3, 2, 7]
husband: [2, 8, 7, 3, 5, 1, 9, 4, 6]
----------
wife : [6, 4, 1, 8, 5, 7, 3, 2, 9]
husband: [3, 8, 7, 2, 5, 1, 6, 4, 9]
----------
wife : [6, 1, 4, 8, 5, 7, 3, 2, 9]
husband: [2, 8, 7, 3, 5, 1, 6, 4, 9]
----------
==========
runtime: 10
solutions: 6
propagators: 346
propagations: 12426
nodes: 67
failures: 28
peak depth: 8
peak memory: 132 KB
Also see My MiniZinc Page for MiniZinc models which may be used with Gecode/FlatZinc.