My Constraint Programming Blog

MiniZinc version 1.5 has been released. It can be downloaded here.

From the NEWS:

G12 MiniZinc Distribution 1.5
-----------------------------

* G12/CPX solver

We have added the solver G12/CPX (Constraint Programming with eXplanations) to the distribution. G12/CPX is the successor to the LazyFD solver. The FlatZinc interface to G12/CPX is named fzn_cpx and MiniZinc models can be solved with G12/CPX using mzn-g12cpx, for example to solve the model foo.mzn using G12/CPX, do

$ mzn-g12cpx foo.mzn

The existing LazyFD solver is now deprecated and will be removed in a future release.

Changes to the MiniZinc language:

* We have added some new built-in functions to assist with formatting complex output: show_int/2, show_float/3, join/2 and concat/1.

* We have added two new built-in functions, show_int/2 and show_float/3, to assist with formatting complex output.

* The built-in annotation is_output/0 is no longer supported.

* The built-in functions sum/1, product/1, forall/1, exists/1, xorall/1 and iffall/1 now also work with multi-dimensional arrays.


Changes to the FlatZinc language:

* We have added two new FlatZinc built-ins: bool_lin_eq/3 and bool_lin_le/3.


Other changes in this release:

* The following new global constraints have been added to the MiniZinc library:
    circuit
    subcircuit

Bugs fixed in this release:

* mzn2fzn now supports flattening expressions containing the built-in operation abort/1.

* mzn2fzn no longer turns optimisation problems that have a fixed objective into satisfaction problems. [Bug #277]

* The FlatZinc interpreter's MIP backend no longer aborts in the presence of a constant assignment to the objective variable. [Bug #319]

* The FlatZinc interpreter's FD backend no longer erroneously reports unsatisfiability in the presence of a constant assignment to the objective variable. [Bug #319]

* mzn2fzn now correctly reports that the built-in fix operation has aborted if given an argument that is not fixed. [Bug #158]

* A bug in mzn2fzn that caused it to not completely flatten array expressions in var array lookups has been fixed. [Bug #318]

* A bug that caused the FlatZinc interpreter to not indicate that search was complete for optimization problems has been fixed.

Quite a few of my MiniZinc models contain is_output (now not supported). I will update to them to the current version as soon as possible.