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

Example 11 with Section

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

the class UnbalancedSectionsTable method createTable.

/**
     * Create report
     * 
     * @param assignment current assignment
     * @param includeLastLikeStudents
     *            true, if last-like students should be included (i.e.,
     *            {@link Student#isDummy()} is true)
     * @param includeRealStudents
     *            true, if real students should be included (i.e.,
     *            {@link Student#isDummy()} is false)
     * @param useAmPm use 12-hour format
     * @return report as comma separated text file
     */
public CSVFile createTable(Assignment<Request, Enrollment> assignment, boolean includeLastLikeStudents, boolean includeRealStudents, boolean useAmPm) {
    CSVFile csv = new CSVFile();
    csv.setHeader(new CSVFile.CSVField[] { new CSVFile.CSVField("Course"), new CSVFile.CSVField("Class"), new CSVFile.CSVField("Meeting Time"), new CSVFile.CSVField("Enrollment"), new CSVFile.CSVField("Target"), new CSVFile.CSVField("Limit"), new CSVFile.CSVField("Disbalance [%]") });
    TreeSet<Offering> offerings = new TreeSet<Offering>(new Comparator<Offering>() {

        @Override
        public int compare(Offering o1, Offering o2) {
            int cmp = o1.getName().compareToIgnoreCase(o2.getName());
            if (cmp != 0)
                return cmp;
            return o1.getId() < o2.getId() ? -1 : o2.getId() == o2.getId() ? 0 : 1;
        }
    });
    offerings.addAll(getModel().getOfferings());
    Offering last = null;
    for (Offering offering : offerings) {
        for (Config config : offering.getConfigs()) {
            double configEnrl = 0;
            for (Enrollment e : config.getEnrollments(assignment)) {
                if (e.getStudent().isDummy() && !includeLastLikeStudents)
                    continue;
                if (!e.getStudent().isDummy() && !includeRealStudents)
                    continue;
                configEnrl += e.getRequest().getWeight();
            }
            for (Subpart subpart : config.getSubparts()) {
                if (subpart.getSections().size() <= 1)
                    continue;
                if (subpart.getLimit() > 0) {
                    // sections have limits -> desired size is section limit x (total enrollment / total limit)
                    double ratio = configEnrl / subpart.getLimit();
                    for (Section section : subpart.getSections()) {
                        double enrl = 0.0;
                        for (Enrollment e : section.getEnrollments(assignment)) {
                            if (e.getStudent().isDummy() && !includeLastLikeStudents)
                                continue;
                            if (!e.getStudent().isDummy() && !includeRealStudents)
                                continue;
                            enrl += e.getRequest().getWeight();
                        }
                        double desired = ratio * section.getLimit();
                        if (Math.abs(desired - enrl) >= Math.max(1.0, 0.1 * section.getLimit())) {
                            if (last != null && !offering.equals(last))
                                csv.addLine();
                            csv.addLine(new CSVFile.CSVField[] { new CSVFile.CSVField(offering.equals(last) ? "" : offering.getName()), new CSVFile.CSVField(section.getSubpart().getName() + " " + section.getName()), new CSVFile.CSVField(section.getTime() == null ? "" : section.getTime().getDayHeader() + " " + section.getTime().getStartTimeHeader(useAmPm) + " - " + section.getTime().getEndTimeHeader(useAmPm)), new CSVFile.CSVField(sDF1.format(enrl)), new CSVFile.CSVField(sDF2.format(desired)), new CSVFile.CSVField(sDF1.format(section.getLimit())), new CSVFile.CSVField(sDF2.format(Math.min(1.0, Math.max(-1.0, (enrl - desired) / section.getLimit())))) });
                            last = offering;
                        }
                    }
                } else {
                    // unlimited sections -> desired size is total enrollment / number of sections
                    for (Section section : subpart.getSections()) {
                        double enrl = 0.0;
                        for (Enrollment e : section.getEnrollments(assignment)) {
                            if (e.getStudent().isDummy() && !includeLastLikeStudents)
                                continue;
                            if (!e.getStudent().isDummy() && !includeRealStudents)
                                continue;
                            enrl += e.getRequest().getWeight();
                        }
                        double desired = configEnrl / subpart.getSections().size();
                        if (Math.abs(desired - enrl) >= Math.max(1.0, 0.1 * desired)) {
                            if (last != null && !offering.equals(last))
                                csv.addLine();
                            csv.addLine(new CSVFile.CSVField[] { new CSVFile.CSVField(offering.equals(last) ? "" : offering.getName()), new CSVFile.CSVField(section.getSubpart().getName() + " " + section.getName()), new CSVFile.CSVField(section.getTime() == null ? "" : section.getTime().getDayHeader() + " " + section.getTime().getStartTimeHeader(useAmPm) + " - " + section.getTime().getEndTimeHeader(useAmPm)), new CSVFile.CSVField(sDF1.format(enrl)), new CSVFile.CSVField(sDF2.format(desired)), new CSVFile.CSVField(""), new CSVFile.CSVField(sDF2.format(Math.min(1.0, Math.max(-1.0, (enrl - desired) / desired)))) });
                            last = offering;
                        }
                    }
                }
            }
        }
    }
    return csv;
}

Example 12 with Section

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

the class Reservation method getRestrictivity.

/**
     * Reservation restrictivity (estimated percentage of enrollments that include this reservation, 1.0 reservation on the whole offering)
     * @return computed restrictivity
     */
public double getRestrictivity() {
    if (iCachedRestrictivity == null) {
        if (getConfigs().isEmpty())
            return 1.0;
        int nrChoices = 0, nrMatchingChoices = 0;
        for (Config config : getOffering().getConfigs()) {
            int[] x = nrChoices(config, 0, new HashSet<Section>(), getConfigs().contains(config));
            nrChoices += x[0];
            nrMatchingChoices += x[1];
        }
        iCachedRestrictivity = ((double) nrMatchingChoices) / nrChoices;
    }
    return iCachedRestrictivity;
}

Example 13 with Section

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

the class Reservation method getLimitCapNoCache.

/**
     * Compute limit cap (maximum number of students that can get into the offering using this reservation)
     */
private double getLimitCapNoCache() {
    // no config -> can be unlimited
    if (getConfigs().isEmpty())
        return -1;
    // can assign over limit -> no cap
    if (canAssignOverLimit())
        return -1;
    // config cap
    double cap = 0;
    for (Config config : iConfigs) cap = add(cap, config.getLimit());
    for (Set<Section> sections : getSections().values()) {
        // subpart cap
        double subpartCap = 0;
        for (Section section : sections) subpartCap = add(subpartCap, section.getLimit());
        // minimize
        cap = min(cap, subpartCap);
    }
    return cap;
}

Example 14 with Section

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

the class EqualStudentWeights method main.

/**
     * Test case -- run to see the weights for a few courses
     * @param args program arguments
     */
public static void main(String[] args) {
    EqualStudentWeights pw = new EqualStudentWeights(new DataProperties());
    DecimalFormat df = new DecimalFormat("0.0000");
    Student s = new Student(0l);
    new CourseRequest(1l, 0, false, s, ToolBox.toList(new Course(1, "A", "1", new Offering(0, "A")), new Course(1, "A", "2", new Offering(0, "A")), new Course(1, "A", "3", new Offering(0, "A"))), false, null);
    new CourseRequest(2l, 1, false, s, ToolBox.toList(new Course(1, "B", "1", new Offering(0, "B")), new Course(1, "B", "2", new Offering(0, "B")), new Course(1, "B", "3", new Offering(0, "B"))), false, null);
    new CourseRequest(3l, 2, false, s, ToolBox.toList(new Course(1, "C", "1", new Offering(0, "C")), new Course(1, "C", "2", new Offering(0, "C")), new Course(1, "C", "3", new Offering(0, "C"))), false, null);
    new CourseRequest(5l, 4, false, s, ToolBox.toList(new Course(1, "E", "1", new Offering(0, "E")), new Course(1, "E", "2", new Offering(0, "E")), new Course(1, "E", "3", new Offering(0, "E"))), false, null);
    new CourseRequest(6l, 5, true, s, ToolBox.toList(new Course(1, "F", "1", new Offering(0, "F")), new Course(1, "F", "2", new Offering(0, "F")), new Course(1, "F", "3", new Offering(0, "F"))), false, null);
    new CourseRequest(7l, 6, true, s, ToolBox.toList(new Course(1, "G", "1", new Offering(0, "G")), new Course(1, "G", "2", new Offering(0, "G")), new Course(1, "G", "3", new Offering(0, "G"))), false, null);
    Assignment<Request, Enrollment> assignment = new DefaultSingleAssignment<Request, Enrollment>();
    Placement p = new Placement(null, new TimeLocation(1, 90, 12, 0, 0, null, null, new BitSet(), 10), new ArrayList<RoomLocation>());
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            w[i] = pw.getWeight(assignment, e, null, null);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]));
    }
    System.out.println("With one distance conflict:");
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            Set<DistanceConflict.Conflict> dc = new HashSet<DistanceConflict.Conflict>();
            dc.add(new DistanceConflict.Conflict(s, e, (Section) sections.iterator().next(), e, (Section) sections.iterator().next()));
            w[i] = pw.getWeight(assignment, e, dc, null);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]));
    }
    System.out.println("With two distance conflicts:");
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            Set<DistanceConflict.Conflict> dc = new HashSet<DistanceConflict.Conflict>();
            dc.add(new DistanceConflict.Conflict(s, e, (Section) sections.iterator().next(), e, (Section) sections.iterator().next()));
            dc.add(new DistanceConflict.Conflict(s, e, (Section) sections.iterator().next(), e, new Section(1, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null)));
            w[i] = pw.getWeight(assignment, e, dc, null);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]));
    }
    System.out.println("With 25% time overlapping conflict:");
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            Set<TimeOverlapsCounter.Conflict> toc = new HashSet<TimeOverlapsCounter.Conflict>();
            toc.add(new TimeOverlapsCounter.Conflict(s, 3, e, sections.iterator().next(), e, sections.iterator().next()));
            w[i] = pw.getWeight(assignment, e, null, toc);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]));
    }
    System.out.println("Disbalanced sections (by 2 / 10 students):");
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            Subpart x = new Subpart(0, "Lec", "Lec", cfg, null);
            Section a = new Section(0, 10, "x", x, p, null);
            new Section(1, 10, "y", x, p, null);
            sections.add(a);
            a.assigned(assignment, new Enrollment(s.getRequests().get(0), i, cfg, sections, assignment));
            a.assigned(assignment, new Enrollment(s.getRequests().get(0), i, cfg, sections, assignment));
            cfg.getContext(assignment).assigned(assignment, new Enrollment(s.getRequests().get(0), i, cfg, sections, assignment));
            cfg.getContext(assignment).assigned(assignment, new Enrollment(s.getRequests().get(0), i, cfg, sections, assignment));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            w[i] = pw.getWeight(assignment, e, null, null);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]));
    }
    System.out.println("Same sections:");
    pw.iMPP = true;
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        double dif = 0;
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            cr.setInitialAssignment(new Enrollment(cr, i, cfg, sections, assignment));
            w[i] = pw.getWeight(assignment, e, null, null);
            dif = pw.getDifference(e);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]) + " (" + df.format(dif) + ")");
    }
    System.out.println("Same choice sections:");
    pw.iMPP = true;
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        double dif = 0;
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            Set<SctAssignment> other = new HashSet<SctAssignment>();
            other.add(new Section(1, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            cr.setInitialAssignment(new Enrollment(cr, i, cfg, other, assignment));
            w[i] = pw.getWeight(assignment, e, null, null);
            dif = pw.getDifference(e);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]) + " (" + df.format(dif) + ")");
    }
    System.out.println("Same time sections:");
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double dif = 0;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            Set<SctAssignment> other = new HashSet<SctAssignment>();
            other.add(new Section(1, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null, new Instructor(1, null, "Josef Novak", null)));
            cr.setInitialAssignment(new Enrollment(cr, i, cfg, other, assignment));
            w[i] = pw.getWeight(assignment, e, null, null);
            dif = pw.getDifference(e);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]) + " (" + df.format(dif) + ")");
    }
    System.out.println("Same configuration sections:");
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        double dif = 0;
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            cr.getSelectedChoices().add(new Choice(cfg));
            cr.setInitialAssignment(null);
            w[i] = pw.getWeight(assignment, e, null, null);
            dif = pw.getDifference(e);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]) + " (" + df.format(dif) + ")");
    }
    System.out.println("Different time sections:");
    Placement q = new Placement(null, new TimeLocation(1, 102, 12, 0, 0, null, null, new BitSet(), 10), new ArrayList<RoomLocation>());
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        double dif = 0;
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            Set<SctAssignment> other = new HashSet<SctAssignment>();
            other.add(new Section(1, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), q, null));
            cr.setInitialAssignment(new Enrollment(cr, i, cfg, other, assignment));
            w[i] = pw.getWeight(assignment, e, null, null);
            dif = pw.getDifference(e);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]) + " (" + df.format(dif) + ")");
    }
    System.out.println("Two sections, one same choice, one same time:");
    for (Request r : s.getRequests()) {
        CourseRequest cr = (CourseRequest) r;
        double[] w = new double[] { 0.0, 0.0, 0.0 };
        double dif = 0;
        for (int i = 0; i < cr.getCourses().size(); i++) {
            Config cfg = new Config(0l, -1, "", cr.getCourses().get(i).getOffering());
            Set<SctAssignment> sections = new HashSet<SctAssignment>();
            sections.add(new Section(0, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            sections.add(new Section(1, 1, "y", new Subpart(1, "Rec", "Rec", cfg, null), p, null));
            Enrollment e = new Enrollment(cr, i, cfg, sections, assignment);
            Set<SctAssignment> other = new HashSet<SctAssignment>();
            other.add(new Section(2, 1, "x", new Subpart(0, "Lec", "Lec", cfg, null), p, null));
            other.add(new Section(3, 1, "y", new Subpart(1, "Rec", "Rec", cfg, null), p, null, new Instructor(1, null, "Josef Novak", null)));
            cr.setInitialAssignment(new Enrollment(cr, i, cfg, other, assignment));
            w[i] = pw.getWeight(assignment, e, null, null);
            dif = pw.getDifference(e);
        }
        System.out.println(cr + ": " + df.format(w[0]) + "  " + df.format(w[1]) + "  " + df.format(w[2]) + " (" + df.format(dif) + ")");
    }
}

Example 15 with Section

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

the class OnlineSectioningCriterion method canImprove.

@Override
public boolean canImprove(Assignment<Request, Enrollment> assignment, int maxIdx, Enrollment[] current, Enrollment[] best) {
    // 0. best priority & alternativity ignoring free time requests
    int alt = 0;
    boolean ft = false;
    for (int idx = 0; idx < current.length; idx++) {
        if (isFreeTime(idx)) {
            ft = true;
            continue;
        }
        Request request = getRequest(idx);
        if (idx < maxIdx) {
            if (best[idx] != null) {
                if (current[idx] == null)
                    // higher priority request assigned
                    return false;
                if (best[idx].getPriority() < current[idx].getPriority())
                    // less alternative request assigned
                    return false;
                if (request.isAlternative())
                    alt--;
            } else {
                if (current[idx] != null)
                    // higher priority request assigned
                    return true;
                if (!request.isAlternative())
                    alt++;
            }
        } else {
            if (best[idx] != null) {
                if (best[idx].getPriority() > 0)
                    // alternativity can be improved
                    return true;
            } else {
                if (!request.isAlternative() || alt > 0)
                    // priority can be improved
                    return true;
            }
        }
    }
    // 0.5. avoid course time overlaps & unavailability overlaps
    if (getModel().getTimeOverlaps() != null) {
        int bestTimeOverlaps = 0, currentTimeOverlaps = 0;
        for (int idx = 0; idx < current.length; idx++) {
            if (best[idx] != null && best[idx].getRequest() instanceof CourseRequest) {
                for (int x = 0; x < idx; x++) {
                    if (best[x] != null && best[x].getRequest() instanceof CourseRequest)
                        bestTimeOverlaps += getModel().getTimeOverlaps().nrConflicts(best[x], best[idx]);
                }
            }
            if (current[idx] != null && idx < maxIdx && current[idx].getRequest() instanceof CourseRequest) {
                for (int x = 0; x < idx; x++) {
                    if (current[x] != null && current[x].getRequest() instanceof CourseRequest)
                        currentTimeOverlaps += getModel().getTimeOverlaps().nrConflicts(current[x], current[idx]);
                }
            }
        }
        for (int idx = 0; idx < current.length; idx++) {
            if (best[idx] != null && best[idx].getAssignments() != null && best[idx].isCourseRequest()) {
                bestTimeOverlaps += getModel().getTimeOverlaps().nrNotAvailableTimeConflicts(best[idx]);
            }
            if (current[idx] != null && idx < maxIdx && current[idx].getAssignments() != null && current[idx].isCourseRequest()) {
                currentTimeOverlaps += getModel().getTimeOverlaps().nrNotAvailableTimeConflicts(current[idx]);
            }
        }
        if (currentTimeOverlaps < bestTimeOverlaps)
            return true;
        if (bestTimeOverlaps < currentTimeOverlaps)
            return false;
    }
    // 1. maximize number of penalties
    double bestPenalties = 0, currentPenalties = 0;
    for (int idx = 0; idx < current.length; idx++) {
        if (best[idx] != null) {
            for (Section section : best[idx].getSections()) bestPenalties += getModel().getOverExpected(assignment, section, best[idx].getRequest());
        }
        if (current[idx] != null && idx < maxIdx) {
            for (Section section : current[idx].getSections()) currentPenalties += getModel().getOverExpected(assignment, section, current[idx].getRequest());
        }
    }
    if (currentPenalties < bestPenalties)
        return true;
    if (bestPenalties < currentPenalties)
        return false;
    // 2. best priority & alternativity including free times
    if (ft) {
        alt = 0;
        for (int idx = 0; idx < current.length; idx++) {
            Request request = getStudent().getRequests().get(idx);
            if (idx < maxIdx) {
                if (best[idx] != null) {
                    if (current[idx] == null)
                        // higher priority request assigned
                        return false;
                    if (best[idx].getPriority() < current[idx].getPriority())
                        // less alternative request assigned
                        return false;
                    if (request.isAlternative())
                        alt--;
                } else {
                    if (current[idx] != null)
                        // higher priority request assigned
                        return true;
                    if (request instanceof CourseRequest && !request.isAlternative())
                        alt++;
                }
            } else {
                if (best[idx] != null) {
                    if (best[idx].getPriority() > 0)
                        // alternativity can be improved
                        return true;
                } else {
                    if (!request.isAlternative() || alt > 0)
                        // priority can be improved
                        return true;
                }
            }
        }
    }
    // 3. maximize selection
    int bestSelected = 0, currentSelected = 0;
    for (int idx = 0; idx < current.length; idx++) {
        if (best[idx] != null && best[idx].isCourseRequest()) {
            Set<Section> preferred = getPreferredSections(best[idx].getRequest());
            if (preferred != null && !preferred.isEmpty()) {
                for (Section section : best[idx].getSections()) if (preferred.contains(section)) {
                    if (idx < maxIdx)
                        bestSelected++;
                } else if (idx >= maxIdx)
                    bestSelected--;
            }
        }
        if (current[idx] != null && idx < maxIdx && current[idx].isCourseRequest()) {
            Set<Section> preferred = getPreferredSections(current[idx].getRequest());
            if (preferred != null && !preferred.isEmpty()) {
                for (Section section : current[idx].getSections()) if (preferred.contains(section))
                    currentSelected++;
            }
        }
    }
    if (currentSelected > bestSelected)
        return true;
    if (bestSelected > currentSelected)
        return false;
    // 3.5 maximize preferences
    double bestSelectedConfigs = 0, currentSelectedConfigs = 0;
    double bestSelectedSections = 0, currentSelectedSections = 0;
    for (int idx = 0; idx < current.length; idx++) {
        if (best[idx] != null && best[idx].getAssignments() != null && best[idx].isCourseRequest()) {
            bestSelectedSections += best[idx].percentSelectedSameSection();
            bestSelectedConfigs += best[idx].percentSelectedSameConfig();
            if (idx >= maxIdx) {
                bestSelectedSections -= 1.0;
                bestSelectedConfigs -= 1.0;
            }
        }
        if (current[idx] != null && idx < maxIdx && current[idx].getAssignments() != null && current[idx].isCourseRequest()) {
            currentSelectedSections += current[idx].percentSelectedSameSection();
            currentSelectedConfigs += current[idx].percentSelectedSameConfig();
        }
    }
    if (0.3 * currentSelectedConfigs + 0.7 * currentSelectedSections > 0.3 * bestSelectedConfigs + 0.7 * bestSelectedSections)
        return true;
    if (0.3 * bestSelectedConfigs + 0.7 * bestSelectedSections > 0.3 * currentSelectedConfigs + 0.7 * currentSelectedSections)
        return false;
    // 4. avoid time overlaps
    if (getModel().getTimeOverlaps() != null) {
        int bestTimeOverlaps = 0, currentTimeOverlaps = 0;
        for (int idx = 0; idx < current.length; idx++) {
            if (best[idx] != null) {
                for (int x = 0; x < idx; x++) {
                    if (best[x] != null)
                        bestTimeOverlaps += getModel().getTimeOverlaps().nrConflicts(best[x], best[idx]);
                    else if (getStudent().getRequests().get(x) instanceof FreeTimeRequest)
                        bestTimeOverlaps += getModel().getTimeOverlaps().nrConflicts(((FreeTimeRequest) getStudent().getRequests().get(x)).createEnrollment(), best[idx]);
                }
            }
            if (current[idx] != null && idx < maxIdx) {
                for (int x = 0; x < idx; x++) {
                    if (current[x] != null)
                        currentTimeOverlaps += getModel().getTimeOverlaps().nrConflicts(current[x], current[idx]);
                    else if (getStudent().getRequests().get(x) instanceof FreeTimeRequest)
                        currentTimeOverlaps += getModel().getTimeOverlaps().nrConflicts(((FreeTimeRequest) getStudent().getRequests().get(x)).createEnrollment(), current[idx]);
                }
            }
        }
        for (int idx = 0; idx < current.length; idx++) {
            if (best[idx] != null && best[idx].getAssignments() != null && best[idx].isCourseRequest()) {
                bestTimeOverlaps += getModel().getTimeOverlaps().nrNotAvailableTimeConflicts(best[idx]);
            }
            if (current[idx] != null && idx < maxIdx && current[idx].getAssignments() != null && current[idx].isCourseRequest()) {
                currentTimeOverlaps += getModel().getTimeOverlaps().nrNotAvailableTimeConflicts(current[idx]);
            }
        }
        if (currentTimeOverlaps < bestTimeOverlaps)
            return true;
        if (bestTimeOverlaps < currentTimeOverlaps)
            return false;
    }
    // 5. avoid distance conflicts
    if (getModel().getDistanceConflict() != null) {
        int bestDistanceConf = 0, currentDistanceConf = 0;
        for (int idx = 0; idx < current.length; idx++) {
            if (best[idx] != null) {
                for (int x = 0; x < idx; x++) {
                    if (best[x] != null)
                        bestDistanceConf += getModel().getDistanceConflict().nrConflicts(best[x], best[idx]);
                }
            }
            if (current[idx] != null && idx < maxIdx) {
                for (int x = 0; x < idx; x++) {
                    if (current[x] != null)
                        currentDistanceConf += getModel().getDistanceConflict().nrConflicts(current[x], current[idx]);
                }
            }
        }
        if (currentDistanceConf < bestDistanceConf)
            return true;
        if (bestDistanceConf < currentDistanceConf)
            return false;
    }
    // 6. avoid no-time sections
    int bestNoTime = 0, currentNoTime = 0;
    for (int idx = 0; idx < current.length; idx++) {
        if (best[idx] != null) {
            for (Section section : best[idx].getSections()) if (section.getTime() == null)
                bestNoTime++;
        }
        if (current[idx] != null && idx < maxIdx) {
            for (Section section : current[idx].getSections()) if (section.getTime() == null)
                currentNoTime++;
        }
    }
    if (currentNoTime < bestNoTime)
        return true;
    if (bestNoTime < currentNoTime)
        return false;
    // 7. balance sections
    double bestUnavailableSize = 0.0, currentUnavailableSize = 0.0;
    int bestAltSectionsWithLimit = 0, currentAltSectionsWithLimit = 0;
    for (int idx = 0; idx < current.length; idx++) {
        if (best[idx] != null) {
            for (Section section : best[idx].getSections()) {
                Subpart subpart = section.getSubpart();
                // skip unlimited and single section subparts
                if (subpart.getSections().size() <= 1 || subpart.getLimit() <= 0)
                    continue;
                // average size
                double averageSize = ((double) subpart.getLimit()) / subpart.getSections().size();
                // section is below average
                if (section.getLimit() < averageSize)
                    bestUnavailableSize += (averageSize - section.getLimit()) / averageSize;
                bestAltSectionsWithLimit++;
            }
        }
        if (current[idx] != null && idx < maxIdx) {
            for (Section section : current[idx].getSections()) {
                Subpart subpart = section.getSubpart();
                // skip unlimited and single section subparts
                if (subpart.getSections().size() <= 1 || subpart.getLimit() <= 0)
                    continue;
                // average size
                double averageSize = ((double) subpart.getLimit()) / subpart.getSections().size();
                // section is below average
                if (section.getLimit() < averageSize)
                    currentUnavailableSize += (averageSize - section.getLimit()) / averageSize;
                currentAltSectionsWithLimit++;
            }
        }
    }
    double bestUnavailableSizeFraction = (bestUnavailableSize > 0 ? bestUnavailableSize / bestAltSectionsWithLimit : 0.0);
    double currentUnavailableSizeFraction = (currentUnavailableSize > 0 ? currentUnavailableSize / currentAltSectionsWithLimit : 0.0);
    if (currentUnavailableSizeFraction < bestUnavailableSizeFraction)
        return true;
    if (bestUnavailableSizeFraction < currentUnavailableSizeFraction)
        return false;
    // 8. average penalty sections
    double bestPenalty = 0.0, currentPenalty = 0.0;
    for (int idx = 0; idx < current.length; idx++) {
        if (best[idx] != null) {
            for (Section section : best[idx].getSections()) bestPenalty += section.getPenalty();
            if (idx >= maxIdx && best[idx].isCourseRequest())
                bestPenalty -= ((CourseRequest) best[idx].getRequest()).getMinPenalty();
        }
        if (current[idx] != null && idx < maxIdx) {
            for (Section section : current[idx].getSections()) currentPenalty += section.getPenalty();
        }
    }
    if (currentPenalty < bestPenalty)
        return true;
    if (bestPenalty < currentPenalty)
        return false;
    return true;
}