4.0.7

JAR file names have changed:

• the suffix 'with-dependencies' disappears,
• the suffix '-no-dep' (for no dependencies) appears.

This should intends to clarify the selection for new comers.

Add a PayPal button for donations.

Move to Ibex-2.6.5.

Major features:

• Revamp Settings: no default method anymore, add setters. A concrete class DefaultSettings provides
  the default behavior.
• IViewFactory.intScaleView now manages negative constants,
• IViewFactory.intAffineView is now available
• add new constraint for mixed linear equation (over real/int variables and double/int coefficients)
• Dow/WDeg now manages variables in a bipartite set (instantiated variables are swaped)
• Assert that a propagator that is passive is not allowed to filter anymore
• An exception is thrown when a sum (or scalar) constraint is candidate for integer over/underflow (an alternative should be provided later)
• BoolVar now handles modifications in different way (may impact performances)
• Propagation engine has changed: no alternative to seven-queue one anymore + simplification of code (may impact performances)
• add new relation expression ift(e1,e2)

Deprecated API (to be removed in next release):

• Model.set(Settings) is deprecated. Now settings are declared in the Model constructor.
• Settings.debugPropagation() is deprecated. There is no alternative.

Closed issues and pull requests:

#527, #564, #569, #576, #578, #581, #586

4.0.6

Move to Ibex-2.6.3.

Major features:

• Ibex instance is no longer static, that offers better stability and reduce
  memory consumption when adding/removing functions. Reification no longer managed by Choco but
  delegated to Ibex.
• Search.realVarSearch(...) offers possibility to define minimal range size, known as epsilon
• Search.ibexSolving(model) let Ibex iterates over solutions once all integer variables are instantiated
• add detection of min/max sub-cases
• add simple dashboard in Swing to show resolution statistics, see solver.showDashboard()

Deprecated API (to be removed in next release):

• IntEqRealConstraint will be removed in next release, Ibex managed this concept (int to real)
• Model.getIbex() should not be used. A IbexHandler manages Ibex instances (one per model).

Closed issues and pull requests:

#558, #561, #565, #566, #568, #570

4.0.5

The current release was submitted to MiniZinc Challenge 2017
and at XCSP3 Competition 2017 and won medals.

choco-parsers provides utility to export a Model to JSON format
and or import JSON data into a Model.

Major features:

• Compact-Table now deals with short tuples (#531)
• Checking if a created constraint is free (neither posted or reified) is now possible with Settings.checkDeclaredConstraints()
• Improvements on BoolVarImpl and BoolNotView.
• Remove code deprecated in last release.
• Fix error in Views.
• Add scalar detection in BiReExpression
• fix errors in Impact-based Search
• update Search.intVarSearch() + Search.defaultSearch(Model)
• update ParallelPortfolio default strategies

Deprecated API (to be removed in next release):

Closed issues and pull requests:

• fix bug in PropNogoods when dealing with negative values (impact solver..setNoGoodRecordingFromRestarts() and solver..setNoGoodRecordingFromSolutions(...))
• fix bug in model.sum(...) and model.scalar(...) when dealing with arity greater than 100 and all operators except =
• fix bug in model.table(...) with binary scope and universal value
• fix bug related to Ibex and GC.

#531 ,#545, #546.

4.0.4

Major features:

• add logical operator to expression (#520). Now it is possible, f-ex., to declare expression like:
  x.eq(y.add(1)).or(x.eq(y).and(x.eq(1)))
• add new API to Solver to print features in a single line
• enable ignoring passivate propagators when iterating over propagators of a modified variable (false by default; see Settings)

Deprecated API (to be removed in next release):

• IPropagationEngine.fails(c,v,m) is replaced by Solver.throwsException(c,v,m) (#524)
• IPropagationEngine.getContradictionException() is replaced by Solver.getContradictionException() (#524)
• MathUtils.bounds(values) is replaced by a call to MathUtils.min(values) and MathUtils.max(values)

Remove dead code:

• SparseSet
• IFeatures, Features, IAttribute and Attribute

Closed issues and pull requests:

#516, #517, #518, #519, #520, #521, #524.

4.0.3

Major features:

• arithm(IntVar,String,IntVar,String,int) and arithm(IntVar,String,IntVar,String,IntVar) manage '*' and '/'
• add new APIs to ArrayUtils
• fix error in PropBoolMin and PropBoolMax

Deprecated API:

Closed issues and pull requests:

#500, #502, #507, #510, #512, #514, #515.

4.0.2

4.0.2 - 20 Jan 2017

Major features:

• restrict calls to Solver.setEngine(...) when propagation started. See javadoc for details.
• remove global constructive disjunction, only local constructive disjunction is allowed.
• add Solution.restore() to restore a solution (#354).
• deep reset of Solver (#490, #491)

Deprecated API:

• Solver.getState() (#485)
• Measures.IN_SEC (related to #486)
• Settings.outputWithANSIColors, IOutputFactory.ANSI_*
• IMoveFactory.setLubyRestart(int, int, ICounter, int)

Closed issues and pull requests:

#468, #479, #480, #481, #484, #487, #488, #489, #492, #493, #494, #495, #496, #497, #499.

4.0.1

This release is the continuation of 4.0.0.

• upgrade CPProfiler monitor to communicate more information (see #458)

Fix issues:

#452 #455 #457 #458 #462 #463 #464 #465 #470 #471 #472 #473 #474 #476 #478

4.0.0

This release is mainly dedicated to API migration. In the following, the major modifications are reported in order to ease code migration.

See also closed issues.

Even though we first wanted to provide an automatic script to help migration, we finally preferred to list the code modifications needed to move from 3 to 4.
The documentation is up-to-date and may be a good starting point.

Note that most IDEs now provide helpful tools to help code migration.

At a glance

In order to distinguish resolution steps, Solver and SearchLoop now move to respectively Model and Solver.

• Model aims at declaring a problem on the basis of variables and constraints, and replaces the dedicated factories.
• Solver mainly focuses on the resolution of the declared problem, using less factories .

In details

• Model
• Variables
  • BoolVar
  • IntVar
  • SetVar
  • RealVar
  • Task
  • Views
• Constraints
  • Refying
  • Clauses
• Solver

Model

v3.3.3	v4.0.0
Solver solver = new Solver("my problem");	Model model = new Model("my problem");

BoolVar

Any BoolVar is now created thanks to model.boolVar(...) APIs.

v3.3.3	v4.0.0
BoolVar x = VF.bool("X", solver);	BoolVar x = model.boolVar("X");
	BoolVar x = model.boolVar();
BoolVar[] xs = VF.boolArray("XS", 4, solver);	BoolVar[] xs = model.boolVar Array("XS", 4);
BoolVar[] xs = VF.boolMatrix("XS", 3, 4, solver);	BoolVar[] xs = model.boolVar Matrix("XS", 3, 4);

IntVar

Any IntVar is now created thanks to model.intVar(...) APIs.

integer

v3.3.3	v4.0.0
IntVar x = VF.integer("X", 0, 10, solver);	IntVar x = model.intVar("X", 0, 10);
	IntVar x = model.intVar(0, 10);
IntVar[] xs = VF.integerArray("XS", 4, 0, 10, solver);	IntVar[] xs = model.intVarArray("XS", 4, 0, 10);
IntVar[] xs = VF.integerMatrix("XS", 3, 4, 0, 10, solver);	IntVar[] xs = model.intVarMatrix("XS", 3, 4, 0, 10);

When one wants to chose between bounded or enumerated, he/she has to set the bounded domain boolean.

bounded

v3.3.3	v4.0.0
IntVar x = VF.bounded("X", 0, 10, solver);	IntVar x = model.intVar("X", 0, 10, true);
	IntVar x = model.intVar(0, 10, true);
IntVar[] xs = VF.boundedArray("XS", 4, 0, 10, solver);	IntVar[] xs = model.intVarArray("XS", 4, 0, 10, true);
IntVar[] xs = VF.boundedMatrix("XS", 3, 4, 0, 10, solver);	IntVar[] xs = model.intVarMatrix("XS", 3, 4, 0, 10, true);

enumerated

v3.3.3	v4.0.0
IntVar x = VF.enumerated("X", 0, 10, solver);	IntVar x = model.intVar("X", 0, 10, false');
	IntVar x = model.intVar(0, 10, false');
IntVar x = VF.enumerated("X", new int[]{0,2,4}, solver);	IntVar x = model.intVar("X", new int[]{0,2,4});
	IntVar x = model.intVar(new int[]{0,2,4});
IntVar xs = VF.enumeratedArray("XS", 4, 0, 10, solver);	IntVar x = model.intVarArray("XS", 0, 10, false');
IntVar xs = VF.enumeratedArray("XS", 4, new int[]{0,2,4}, solver);	IntVar x = model.intVarArray("XS", new int[]{0,2,4});
IntVar xs = VF.enumeratedMatrix("XS", 3, 4, 0, 10, solver);	IntVar x = model.intVarMatrix("X", 3, 4, 0, 10, false');
IntVar xs = VF.enumeratedMatrix("XS", 3, 4, new int[]{0,2,4}, solver);	IntVar x = model.intVarMatrix("X", 3, 4, new int[]{0,2,4});

fixed

The way constants are declared does not depend on the type (fixed or variable) but on the kind (integer, set, ...).

v3.3.3	v4.0.0
IntVar zero = VariableFactory.fixed(0, solver);	IntVar zero = model.intVar(0);
IntVar zero = VariableFactory.fixed("0", 0, solver);	IntVar zero = model.intVar("0", 0);

SetVar and RealVar

Similar modifications were applied to SetVar and RealVar declaration, e.g.:

v3.3.3	v4.0.0
SetVar s = VariableFactory.set("S", new int[]{0,3}, new int[]{0, 1, 2, 3}, solver);	SetVar s = model.setVar("S", new int[]{0,3}, new int[]{0, 1, 2, 3});
RealVar r = VariableFactory.real("R", 0.1d, 2.2d, solver);	RealVar r = model.realVar("R", 0.1d, 2.2d);

Task

A TaskVar now have to be created calling new Task(IntVar start, IntVar duration, IntVar end).

Views

Ways to create views evolved too, the signature are now :

• model.intAbsView(IntVar),
• model.intMinusView(IntVar),
• model.intOffsetView(IntVar),
• model.intScaleView(IntVar),
• model.boolNotView(IntVar),
• model.realIntView(IntVar)

Constraints

Constraints can be created thanks to a model.
For example,

solver.post(IntConstraintFactory.alldifferent(xs));

now becomes:

model.post(model.allDifferent(xs));

or, in a more convenient way:

model.allDifferent(xs).post();

Most of the names and signatures remain the same between the two versions (but not all, see for instance alldifferent is now allDifferent).

Reifying

Nothing really change here, expect the way constraints are created:

BoolVar b = model.allDifferent(xs).reify();

Note that Model provides APIs like model.ifThenElse(Constraint, Constraint, Constraint).

Clauses

Model offers possibilities to directly add clauses to the clause-store, like model.addClauses***(...) where *** indicates the expression to turn into clauses.

Solver

SearchLoop now becomes Solver.

Solver solver = model.getSolver();

This class provides APIs to configure the search and the resolution process.

v3.3.3 APIs to solve problem, like solver.findSolution().
However, the returning value has changed, from boolean to Solution.

Solver now provides another API to solve a problem, named solve() which looks for a feasible solution.
It can be called as long as it returns true. In that case, the resolution process stops on a solution state, which means that variables are instantiated and their domain can be read.

Printing solutions or resolution statistics is not done thanks to a factory anymore, but directly with the solver, e.g.:
solver.showDecisions();

The same goes with measures, directly reachable from the solver, e.g:
solver.getBackTrackCount();

Solver hasReachedLimit() moved to isStopCriterionMet() (since limit were renamed criterion so far, both method act similarly).
Moreover, Solver.getState() which returns one of those states:

• NEW: when the problem is established but the resolution has not been triggered yet ;
• RUNNING: when the solver is searching for a solution ;
• TERMINATED: the search ends normally, a solution is found or the entire search tree was explored without finding any solution ;
• STOPPED : the search was stopped by a limit ;
• KILLED : the resolution was killed from the outside (eg, thread interruption, JVM killed)

Solver's setters signatures have changed to be more accurate, e.g.:
solver.set(mySearchStrategy) becomes solver.setSearch(mySearchStrategy)

IntSearchStrategy and similar were merged into Search, which provides widely used search strategies.
Making dedicated combination of variable selector and value selector may imply to create object calling new instruction.

Closed issues

#427, #433, #438, #448, #450, #456

4.0.0.a

This is a pre-release of version 4.0.0.
This version is about a deep refactoring of the API, on modeling part mainly, but not only.

3.3.3

3.3.3 - 22 Dec 2015

All:

• remove deprecated interfaces, classes and methods.

Solver:

• add new APIs with an argument named restoreLastSolution which allow to indicate
  whether or not the last solution found, if any, should be restored on exit;
  Previous APIs (without the argument) restore the last solution by default (#354)
• update javadoc (in particular: #347)
• add default name to Solver + setter, modify measures printing to include the name.
• SetVar toString implementation has changed

Explanations

• refactor PropNogoods to deal with generalized no-goods

Bug fixes:

#346, #348, #349, #350, #351, #352, #353, #354, #355, #356, #357, #358, #359