[gecode-users] Gecode 4.0.0

[Christian Schulte]

Dear all,

As this year has already a number of releases of Gecode from the 3.* version
series we have decided to slow the pace and prepare for Gecode 4.0.0 as the
next major release.

This mail is just to assure you that we are not dormant but that it will
take longer before the next version appears. If there is the need for a bug
fix release we will of course do that in the meantime.

Our current plan is to include the following features:

- Integrate propagator groups, see here:
	
http://web.it.kth.se/~cschulte/paper.php?id=LagerkvistSchulte:CP:2009

- Integrate lightweight dynamic symmetry breaking, see here:
	Lightweight Dynamic Symmetry Breaking.  C. Mears, M. Garcia de la
Banda, B. Demoen, M. Wallace.
     SymCon'08.
   LDSB is a dynamic symmetry breaking method designed to handle
   common symmetries efficiently under any variable and value
   ordering.

- Integrate float variables

- Provide modeling layer for float variables

- Support for restarts during search and large neighborhood search

- Make randomized tie-breaking more flexible

- Modeling layer for scheduling constraints

- Branching for scheduling problems


Some more speculative things that might or might not make it are:

- Integrate discrepancy-based search that is not LDS (?)

- Half-reification, see here:
	Thibaut Feydy, Zoltan Somogyi, Peter J. Stuckey: Half Reification
and Flattening. CP 2011: 286-301

- Redundancy analysis, see here:
	http://web.it.kth.se/~cschulte/paper.php?id=SchulteStuckey:PPDP:2008

Best
Christian

--
Christian Schulte, www.ict.kth.se/~cschulte/