Examples with WeakeningConstraint org.cpsolver.ifs.model.WeakeningConstraint used on opensource projects

Example 1 with WeakeningConstraint

use of org.cpsolver.ifs.model.WeakeningConstraint in project cpsolver by UniTime.

the class GroupConstraint method forwardCheck.

public boolean forwardCheck(Assignment<Lecture, Placement> assignment, Placement value, Set<GroupConstraint> ignore, int depth) {
    try {
        if (depth < 0)
            return true;
        ignore.add(this);
        int neededSize = value.variable().maxRoomUse();
        for (Lecture lecture : variables()) {
            // Skip this lecture
            if (lecture.equals(value.variable()))
                continue;
            Placement current = assignment.getValue(lecture);
            if (current != null) {
                // Has assignment, check whether it is conflicting
                if (isSatisfiedPair(assignment, value, current)) {
                    // Increase needed size if the assignment is of the same room and overlapping in time
                    if (canShareRoom() && sameRoomAndOverlaps(value, current)) {
                        neededSize += lecture.maxRoomUse();
                    }
                    continue;
                }
                return false;
            }
            // Look for supporting assignments assignment
            boolean shareRoomAndOverlaps = canShareRoom();
            Placement support = null;
            int nrSupports = 0;
            if (lecture.nrValues() >= iForwardCheckMaxDomainSize) {
                // ignore variables with large domains
                return true;
            }
            List<Placement> values = lecture.values(assignment);
            if (values.isEmpty()) {
                // ignore variables with empty domain
                return true;
            }
            for (Placement other : lecture.values(assignment)) {
                if (nrSupports < 2) {
                    if (isSatisfiedPair(assignment, value, other)) {
                        if (support == null)
                            support = other;
                        nrSupports++;
                        if (shareRoomAndOverlaps && !sameRoomAndOverlaps(value, other))
                            shareRoomAndOverlaps = false;
                    }
                } else if (shareRoomAndOverlaps && !sameRoomAndOverlaps(value, other) && isSatisfiedPair(assignment, value, other)) {
                    shareRoomAndOverlaps = false;
                }
                if (nrSupports > 1 && !shareRoomAndOverlaps)
                    break;
            }
            // No supporting assignment -> fail
            if (nrSupports == 0) {
                // other class cannot be assigned with this value
                return false;
            }
            // Increase needed size if all supporters are of the same room and in overlapping times
            if (shareRoomAndOverlaps) {
                neededSize += lecture.maxRoomUse();
            }
            // Only one supporter -> propagate the new assignment over other hard constraints of the lecture
            if (nrSupports == 1) {
                for (Constraint<Lecture, Placement> other : lecture.hardConstraints()) {
                    if (other instanceof WeakeningConstraint)
                        continue;
                    if (other instanceof GroupConstraint) {
                        GroupConstraint gc = (GroupConstraint) other;
                        if (depth > 0 && !ignore.contains(gc) && !gc.forwardCheck(assignment, support, ignore, depth - 1))
                            return false;
                    } else {
                        if (other.inConflict(assignment, support))
                            return false;
                    }
                }
                for (GlobalConstraint<Lecture, Placement> other : getModel().globalConstraints()) {
                    if (other instanceof WeakeningConstraint)
                        continue;
                    if (other.inConflict(assignment, support))
                        return false;
                }
            }
        }
        if (canShareRoom() && neededSize > value.getRoomSize()) {
            // room is too small to fit all meet with classes
            return false;
        }
        return true;
    } finally {
        ignore.remove(this);
    }
}

Example 2 with WeakeningConstraint

use of org.cpsolver.ifs.model.WeakeningConstraint in project cpsolver by UniTime.

the class GroupConstraint method forwardCheck.

public void forwardCheck(Assignment<Lecture, Placement> assignment, Placement value, Set<Placement> conflicts, Set<GroupConstraint> ignore, int depth) {
    try {
        if (depth < 0)
            return;
        ignore.add(this);
        List<Placement> neededSize = null;
        for (Lecture lecture : variables()) {
            // already conflicting
            if (conflicts.contains(value))
                break;
            // Skip this lecture
            if (lecture.equals(value.variable()))
                continue;
            Placement current = assignment.getValue(lecture);
            if (current != null) {
                // Has assignment, check whether it is conflicting
                if (isSatisfiedPair(assignment, value, current)) {
                    // Increase needed size if the assignment is of the same room and overlapping in time
                    if (canShareRoom() && sameRoomAndOverlaps(value, current)) {
                        if (neededSize == null)
                            neededSize = new ArrayList<Placement>();
                        neededSize.add(current);
                    }
                    continue;
                }
                conflicts.add(current);
            }
            // Look for supporting assignments assignment
            boolean shareRoomAndOverlaps = canShareRoom();
            Placement support = null;
            int nrSupports = 0;
            if (lecture.nrValues() >= iForwardCheckMaxDomainSize) {
                // ignore variables with large domains
                return;
            }
            List<Placement> values = lecture.values(assignment);
            if (values.isEmpty()) {
                // ignore variables with empty domain
                return;
            }
            for (Placement other : values) {
                if (nrSupports < 2) {
                    if (isSatisfiedPair(assignment, value, other)) {
                        if (support == null)
                            support = other;
                        nrSupports++;
                        if (shareRoomAndOverlaps && !sameRoomAndOverlaps(value, other))
                            shareRoomAndOverlaps = false;
                    }
                } else if (shareRoomAndOverlaps && !sameRoomAndOverlaps(value, other) && isSatisfiedPair(assignment, value, other)) {
                    shareRoomAndOverlaps = false;
                }
                if (nrSupports > 1 && !shareRoomAndOverlaps)
                    break;
            }
            // No supporting assignment -> fail
            if (nrSupports == 0) {
                // other class cannot be assigned with this value
                conflicts.add(value);
                return;
            }
            // Increase needed size if all supporters are of the same room and in overlapping times
            if (shareRoomAndOverlaps && support != null) {
                if (neededSize == null)
                    neededSize = new ArrayList<Placement>();
                neededSize.add(support);
            }
            // Only one supporter -> propagate the new assignment over other hard constraints of the lecture
            if (nrSupports == 1) {
                for (Constraint<Lecture, Placement> other : lecture.hardConstraints()) {
                    if (other instanceof WeakeningConstraint)
                        continue;
                    if (other instanceof GroupConstraint) {
                        GroupConstraint gc = (GroupConstraint) other;
                        if (depth > 0 && !ignore.contains(gc))
                            gc.forwardCheck(assignment, support, conflicts, ignore, depth - 1);
                    } else {
                        other.computeConflicts(assignment, support, conflicts);
                    }
                }
                for (GlobalConstraint<Lecture, Placement> other : getModel().globalConstraints()) {
                    if (other instanceof WeakeningConstraint)
                        continue;
                    other.computeConflicts(assignment, support, conflicts);
                }
                if (conflicts.contains(support))
                    conflicts.add(value);
            }
        }
        if (canShareRoom() && neededSize != null) {
            if (value.getRoomLocations() != null) {
                for (RoomLocation room : value.getRoomLocations()) if (room.getRoomConstraint() != null && !room.getRoomConstraint().checkRoomSize(value, neededSize)) {
                    // room is too small to fit all meet with classes
                    conflicts.add(value);
                }
            } else if (value.getRoomLocation() != null) {
                RoomLocation room = value.getRoomLocation();
                if (room.getRoomConstraint() != null && !room.getRoomConstraint().checkRoomSize(value, neededSize)) {
                    // room is too small to fit all meet with classes
                    conflicts.add(value);
                }
            }
        }
    } finally {
        ignore.remove(this);
    }
}

Example 3 with WeakeningConstraint

use of org.cpsolver.ifs.model.WeakeningConstraint in project cpsolver by UniTime.

the class Lecture method removeContstraint.

@Override
public void removeContstraint(Constraint<Lecture, Placement> constraint) {
    super.removeContstraint(constraint);
    if (constraint instanceof WeakeningConstraint)
        iWeakeningConstraints.remove(constraint);
    if (constraint instanceof FlexibleConstraint)
        iFlexibleGroupConstraints.remove(constraint);
    if (constraint instanceof JenrlConstraint) {
        JenrlConstraint jenrl = (JenrlConstraint) constraint;
        Lecture another = jenrl.another(this);
        if (another != null) {
            iJenrlConstraints.remove(jenrl);
            another.iJenrlConstraints.remove(jenrl);
            iJenrlConstraintsHash.remove(another);
            another.iJenrlConstraintsHash.remove(this);
        }
    } else if (constraint instanceof GroupConstraint) {
        iCanShareRoomGroupConstraints.remove(constraint);
        iHardGroupSoftConstraints.remove(constraint);
        iGroupConstraints.remove(constraint);
    } else if (constraint instanceof DepartmentSpreadConstraint)
        iDeptSpreadConstraint = null;
    else if (constraint instanceof SpreadConstraint)
        iSpreadConstraints.remove(constraint);
    else if (constraint instanceof InstructorConstraint)
        iInstructorConstraints.remove(constraint);
    else if (constraint instanceof ClassLimitConstraint)
        iClassLimitConstraint = null;
}

Example 4 with WeakeningConstraint

use of org.cpsolver.ifs.model.WeakeningConstraint in project cpsolver by UniTime.

the class Lecture method addContstraint.

@Override
public void addContstraint(Constraint<Lecture, Placement> constraint) {
    super.addContstraint(constraint);
    if (constraint instanceof WeakeningConstraint)
        iWeakeningConstraints.add(constraint);
    if (constraint instanceof FlexibleConstraint)
        iFlexibleGroupConstraints.add((FlexibleConstraint) constraint);
    if (constraint instanceof JenrlConstraint) {
        JenrlConstraint jenrl = (JenrlConstraint) constraint;
        Lecture another = jenrl.another(this);
        if (another != null) {
            iJenrlConstraints.add(jenrl);
            another.iJenrlConstraints.add(jenrl);
            iJenrlConstraintsHash.put(another, (JenrlConstraint) constraint);
            another.iJenrlConstraintsHash.put(this, (JenrlConstraint) constraint);
        }
    } else if (constraint instanceof DepartmentSpreadConstraint)
        iDeptSpreadConstraint = (DepartmentSpreadConstraint) constraint;
    else if (constraint instanceof SpreadConstraint)
        iSpreadConstraints.add((SpreadConstraint) constraint);
    else if (constraint instanceof InstructorConstraint) {
        InstructorConstraint ic = (InstructorConstraint) constraint;
        if (ic.getResourceId() != null && ic.getResourceId().longValue() > 0)
            iInstructorConstraints.add(ic);
    } else if (constraint instanceof ClassLimitConstraint)
        iClassLimitConstraint = (ClassLimitConstraint) constraint;
    else if (constraint instanceof GroupConstraint) {
        GroupConstraint gc = (GroupConstraint) constraint;
        if (gc.canShareRoom()) {
            iCanShareRoomGroupConstraints.add((GroupConstraint) constraint);
        } else {
            iGroupConstraints.add((GroupConstraint) constraint);
            if (Constants.sPreferenceProhibited.equals(Constants.preferenceLevel2preference(gc.getPreference())) || Constants.sPreferenceRequired.equals(Constants.preferenceLevel2preference(gc.getPreference())))
                iHardGroupSoftConstraints.add((GroupConstraint) constraint);
        }
    }
}