Examples with Request org.cpsolver.studentsct.model.Request used on opensource projects

Example 41 with Request

use of org.cpsolver.studentsct.model.Request in project cpsolver by UniTime.

the class BacktrackSelection method init.

public void init(Solver<Request, Enrollment> solver, String name) {
    List<Request> variables = new ArrayList<Request>(iIncludeAssignedRequests ? solver.currentSolution().getModel().variables() : solver.currentSolution().getModel().unassignedVariables(solver.currentSolution().getAssignment()));
    Collections.shuffle(variables);
    iRequests = new LinkedList<Request>(variables);
    if (iRBtNSel == null) {
        try {
            iRBtNSel = new RandomizedBacktrackNeighbourSelection(solver.getProperties());
            iRBtNSel.init(solver);
        } catch (Exception e) {
            throw new RuntimeException(e.getMessage(), e);
        }
    }
    Progress.getInstance(solver.currentSolution().getModel()).setPhase(name, variables.size());
}

Example 42 with Request

use of org.cpsolver.studentsct.model.Request in project cpsolver by UniTime.

the class Test method updateSpace.

public static void updateSpace(Assignment<Request, Enrollment> assignment, Enrollment enrollment, boolean increment) {
    if (enrollment == null || !enrollment.isCourseRequest())
        return;
    for (Section section : enrollment.getSections()) section.setSpaceHeld(section.getSpaceHeld() + (increment ? 1.0 : -1.0));
    List<Enrollment> feasibleEnrollments = new ArrayList<Enrollment>();
    int totalLimit = 0;
    for (Enrollment enrl : enrollment.getRequest().values(assignment)) {
        if (!enrl.getCourse().equals(enrollment.getCourse()))
            continue;
        boolean overlaps = false;
        for (Request otherRequest : enrollment.getRequest().getStudent().getRequests()) {
            if (otherRequest.equals(enrollment.getRequest()) || !(otherRequest instanceof CourseRequest))
                continue;
            Enrollment otherErollment = assignment.getValue(otherRequest);
            if (otherErollment == null)
                continue;
            if (enrl.isOverlapping(otherErollment)) {
                overlaps = true;
                break;
            }
        }
        if (!overlaps) {
            feasibleEnrollments.add(enrl);
            if (totalLimit >= 0) {
                int limit = enrl.getLimit();
                if (limit < 0)
                    totalLimit = -1;
                else
                    totalLimit += limit;
            }
        }
    }
    double change = enrollment.getRequest().getWeight() / (totalLimit > 0 ? totalLimit : feasibleEnrollments.size());
    for (Enrollment feasibleEnrollment : feasibleEnrollments) for (Section section : feasibleEnrollment.getSections()) {
        if (totalLimit > 0) {
            section.setSpaceExpected(section.getSpaceExpected() + (increment ? +change : -change) * feasibleEnrollment.getLimit());
        } else {
            section.setSpaceExpected(section.getSpaceExpected() + (increment ? +change : -change));
        }
    }
}

Example 43 with Request

use of org.cpsolver.studentsct.model.Request in project cpsolver by UniTime.

the class EnrollmentSelection method isAllowed.

/** true, if it is allowed to assign given value 
     * @param assignment current assignment
     * @param value given value
     * @param conflicts conflicting assignments
     * @return true if it is allowed
     **/
public boolean isAllowed(Assignment<Request, Enrollment> assignment, Enrollment value, Set<Enrollment> conflicts) {
    if (value == null)
        return true;
    StudentSectioningModel model = (StudentSectioningModel) value.variable().getModel();
    if (model.getNrLastLikeRequests(false) == 0 || model.getNrRealRequests(false) == 0)
        return true;
    Request request = value.variable();
    if (request.getStudent().isDummy()) {
        if (conflicts == null)
            conflicts = value.variable().getModel().conflictValues(assignment, value);
        for (Enrollment conflict : conflicts) {
            if (!conflict.getRequest().getStudent().isDummy())
                return false;
        }
    } else {
        if (conflicts == null)
            conflicts = value.variable().getModel().conflictValues(assignment, value);
        if (conflicts.size() > (assignment.getValue(request) == null ? 1 : 0))
            return false;
    }
    return true;
}

Example 44 with Request

use of org.cpsolver.studentsct.model.Request in project cpsolver by UniTime.

the class OnlineSelection method updateSpace.

/** Update online sectioning info after the given student is sectioned 
     * @param assignment current assignment
     * @param student student in question
     **/
public void updateSpace(Assignment<Request, Enrollment> assignment, Student student) {
    for (Request request : student.getRequests()) {
        if (!(request instanceof CourseRequest))
            continue;
        CourseRequest courseRequest = (CourseRequest) request;
        Enrollment enrollment = assignment.getValue(courseRequest);
        if (enrollment == null)
            // not enrolled --> no update
            return;
        for (Section section : enrollment.getSections()) {
            section.setSpaceHeld(section.getSpaceHeld() - courseRequest.getWeight());
        // sLog.debug("  -- space held for "+section+" decreased by 1 (to "+section.getSpaceHeld()+")");
        }
        List<Enrollment> feasibleEnrollments = new ArrayList<Enrollment>();
        for (Enrollment enrl : courseRequest.values(assignment)) {
            boolean overlaps = false;
            for (Request otherRequest : courseRequest.getStudent().getRequests()) {
                if (otherRequest.equals(courseRequest) || !(otherRequest instanceof CourseRequest))
                    continue;
                Enrollment otherErollment = assignment.getValue(otherRequest);
                if (otherErollment == null)
                    continue;
                if (enrl.isOverlapping(otherErollment)) {
                    overlaps = true;
                    break;
                }
            }
            if (!overlaps)
                feasibleEnrollments.add(enrl);
        }
        double decrement = courseRequest.getWeight() / feasibleEnrollments.size();
        for (Enrollment feasibleEnrollment : feasibleEnrollments) {
            for (Section section : feasibleEnrollment.getSections()) {
                section.setSpaceExpected(section.getSpaceExpected() - decrement);
            // sLog.debug("  -- space expected for "+section+" decreased by "+decrement+" (to "+section.getSpaceExpected()+")");
            }
        }
    }
}

Example 45 with Request

use of org.cpsolver.studentsct.model.Request in project cpsolver by UniTime.

the class PriorityConstructionSelection method branchAndBound.

/**
     * Find best solution for the next student using {@link BranchBoundSelection}.
     * @param solution current selection
     * @return generated neighbour
     */
public Neighbour<Request, Enrollment> branchAndBound(Solution<Request, Enrollment> solution) {
    while (iStudentsEnumeration.hasNext()) {
        Student student = iStudentsEnumeration.next();
        Progress.getInstance(solution.getModel()).incProgress();
        /*
            if (student.nrRequests() < iCycle) {
                // not enough requests -> nothing to improve -> skip
                continue;
            }
            if (student.nrAssignedRequests() + 1 < iCycle) {
                // previous step cycle already did not improve the assignment -> skip
                continue;
            }
            */
        Neighbour<Request, Enrollment> neighbour = iBranchBoundSelection.getSelection(solution.getAssignment(), student).select();
        if (neighbour != null)
            return neighbour;
    }
    return null;
}