Re: [Choco-users] solveAll() bug?

[Varun J. <jai...@ho...>]

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Hi,Thank you very much for your quick reply. I=0A=
guess the real question I wanted to ask was that if choco could return=0A=
results even when the problem is infeasible. I did my experiment with=0A=
the following problem:------------------------------------------------Varia=
bles:Variable0, Domain: {3, 1, 4}Variable1, Domain: {2, 4, 6}Variable2, Dom=
ain: {2, 1}Variable3, Domain: {3, 1}Variable4, Domain: {6, 2, 5}Constraints=
:Constraint0, on variables 2 , Allowed values:2Constraint1, on variables 2,=
 4 , Allowed values:1, 62, 2Constraint2, on variables 4, 2 , Allowed values=
:5, 2Constraint3, on variables 1, 3 , Allowed values:2, 3------------------=
------------------------------------All=0A=
the constraints were created using Problem.makeTupleFC(IntVar[]=0A=
varList, ArrayList tuples, boolean feasible). For example, the first=0A=
constraint can be created as follows:--------------------------------------=
----Problem chocoCSP;/** * Set up the variables using chocoCSP.makeEnumIntV=
ar() */IntVar[] varList =3D new IntVar[1];varList[0] =3D variables[2];Array=
List<int[]> tuples =3D new ArrayList<int[]>();tuples.add(new int[]{2});choc=
oCSP.makeTupleFC(varList, tuples, true);-----------------------------------=
--------------To obtain solutions, I did the following:--------------------=
---------------------------    System.out.println("SolveAll says: " + choco=
CSP.solveAll());    System.out.println("isFeasible says: " + chocoCSP.isFea=
sible());    System.out.println("Choco Solutions");    if(chocoCSP.solve() =
=3D=3D Boolean.TRUE) {      do {        for(int i =3D 0; i < chocoCSP.getNb=
IntVars(); i ++) {          System.out.print(((IntDomainVar) chocoCSP.getIn=
tVar(i)).getVal() + ", ");        }        System.out.println();      } whi=
le(chocoCSP.nextSolution() =3D=3D Boolean.TRUE);    }----------------------=
-------------------------Here is the output:SolveAll says: trueisFeasible s=
ays: falseChoco Solutions1,2,2,3,5,3,2,2,3,5,4,2,2,3,5,Clearly,=0A=
the solutions do not satisfy all the constraints. For instance, none of=0A=
the solutions satisfy Constraint1. Is this expected behaviour??Thanks again=
,-Varun.> Date: Fri, 17 Nov 2006 11:31:40 +0100> From: Guillaume.Richaud@em=
n.fr> To: jai...@ho...> Subject: Re: [Choco-users] solveAll() bug=
?> > Hi,> > I am not sure to understand what you try to do but i have some =
answers :)> -SolveAll still return true (it is hardcoded) but you can modif=
y the > function solveAll() in choco.Problem> > In choco.Problem:>   public=
 Boolean solveAll() {>     solver.firstSolution =3D false;>     solver.gene=
rateSearchSolver(this);>     solver.launch();>     return Boolean.TRUE;>   =
}> > -What kind of error do you have ? How do you implement the > nextSolut=
ion() loop ?> BTW, if you use nextSolution() to display solutions, you can =
use instead:> > "Solver.setVerbosity(Solver.SOLUTION);" before to begin to =
solve> and "Solver.flushLogs();" to print solutions> > else:> > if (pb.solv=
e() =3D=3D Boolean.TRUE) {> >   do {> 	//Code>     }>   } while(pb.nextSolu=
tion() =3D=3D Boolean.TRUE);> }> > > I hope it helps you... :)> -Guillaume>=
 > Varun Jain a =E9crit :> > Hi..> > Is there any reason why the solveAll()=
 method will return true even if > > there is no solution that satisfies al=
l constraints. I was getting > > this behaviour so I did a little experimen=
t: I set up a simple problem > > and executed the following: > >  > > Probl=
em chocoCSP; > > //............... > > //-----Set up the problem > > //....=
........... > > System.out.println("SolveAll says: " + chocoCSP.solveAll())=
; > > System.out.println("isFeasible says: " + chocoCSP.isFeasible()); > > =
 > > The following was the output > >  > > SolveAll says: true > > isFeasib=
le says: false > >  > > I thought solveAll() returns false if no solution e=
xists. Also, for > > this problem, the solutions I get from the nextSolutio=
n() method do > > not satisfy all constraints. Any explainations would be r=
eally helpful? > >  > > Thanks, > > -Varun. >=20
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