001package org.cpsolver.coursett.criteria.additional;
002
003import java.util.Collection;
004import java.util.Map;
005
006import org.cpsolver.coursett.constraint.JenrlConstraint;
007import org.cpsolver.coursett.criteria.StudentConflict;
008import org.cpsolver.coursett.model.Lecture;
009import org.cpsolver.coursett.model.Placement;
010import org.cpsolver.coursett.model.Student;
011import org.cpsolver.ifs.assignment.Assignment;
012import org.cpsolver.ifs.criteria.Criterion;
013import org.cpsolver.ifs.util.DataProperties;
014
015
016/**
017 * Instructor student conflicts. This criterion penalizes cases when an instructor (of a class) is attending some 
018 * other class as a student and there is a conflict between the two classes.
019 * <br>
020 * To enable instructor student conflicts, set solver parameter Global.LoadStudentInstructorConflicts to true. Also
021 * student course requests should be used in this case (to be able to match an instructor external id to a student 
022 * external id).
023 * <br>
024 * Instructor student conflicts are weighted by Comparator.InstructorStudentConflictWeight.
025 *   
026 * <br>
027 * 
028 * @author  Tomáš Müller
029 * @version CourseTT 1.3 (University Course Timetabling)<br>
030 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
031 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
032 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
033 * <br>
034 *          This library is free software; you can redistribute it and/or modify
035 *          it under the terms of the GNU Lesser General Public License as
036 *          published by the Free Software Foundation; either version 3 of the
037 *          License, or (at your option) any later version. <br>
038 * <br>
039 *          This library is distributed in the hope that it will be useful, but
040 *          WITHOUT ANY WARRANTY; without even the implied warranty of
041 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
042 *          Lesser General Public License for more details. <br>
043 * <br>
044 *          You should have received a copy of the GNU Lesser General Public
045 *          License along with this library; if not see
046 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
047 */
048public class InstructorStudentConflict extends StudentConflict {
049    
050    /**
051     * Only count students that are instructors assigned to one of the two classes and enrolled in the other.
052     */
053    @Override
054    protected double jointEnrollment(JenrlConstraint jenrl) {
055        double ret = 0.0;
056        for (Student student: jenrl.getInstructors())
057            ret += student.getJenrlWeight(jenrl.first(), jenrl.second());
058        return ret;
059    }
060    
061    @Override
062    public boolean isApplicable(Lecture l1, Lecture l2) {
063        return l1 != null && l2 != null && !ignore(l1, l2) && applicable(l1, l2) && instructor(l1, l2);
064    }
065    
066    /**
067     * True if there is at least one student teaching one of the two classes and enrolled in the other.
068     * @param l1 first lecture
069     * @param l2 second lecture
070     * @return true if there is at least one student of one class teaching the other class
071     */
072    public boolean instructor(Lecture l1, Lecture l2) {
073        JenrlConstraint jenrl = (l1 == null || l2 == null ? null : l1.jenrlConstraint(l2));
074        if (jenrl == null) return false;
075        return jenrl.getNrInstructors() > 0;
076    }
077    
078    @Override
079    public void incJenrl(Assignment<Lecture, Placement> assignment, JenrlConstraint jenrl, double studentWeight, Double conflictPriority, Student student) {
080        if (isApplicable(jenrl.first(), jenrl.second()) && inConflict(assignment.getValue(jenrl.first()), assignment.getValue(jenrl.second())) && student.getInstructor() != null
081                && (student.getInstructor().variables().contains(jenrl.first()) || student.getInstructor().variables().contains(jenrl.second())))
082            inc(assignment, studentWeight);
083    }
084    
085    @Override
086    public double getWeightDefault(DataProperties config) {
087        return config.getPropertyDouble("Comparator.InstructorStudentConflictWeight", 10.0 * config.getPropertyDouble("Comparator.StudentConflictWeight", 1.0));
088    }
089    
090    @Override
091    public String getPlacementSelectionWeightName() {
092        return "Placement.NrInstructorStudConfsWeight";
093    }
094
095    @Override
096    public void getInfo(Assignment<Lecture, Placement> assignment, Map<String, String> info) {
097        super.getInfo(assignment, info);
098        double conf = getValue(assignment);
099        if (conf > 0.0) {
100            Criterion<Lecture, Placement> c = getModel().getCriterion(InstructorStudentHardConflict.class);
101            double hard = (c == null ? 0.0 : c.getValue(assignment));
102            info.put("Instructor student conflicts", sDoubleFormat.format(conf) + (hard > 0.0 ? " [hard: " + sDoubleFormat.format(hard) + "]" : ""));
103        }
104    }
105    
106    @Override
107    public void getInfo(Assignment<Lecture, Placement> assignment, Map<String, String> info, Collection<Lecture> variables) {
108        super.getInfo(assignment, info, variables);
109        double conf = getValue(assignment, variables);
110        if (conf > 0.0) {
111            Criterion<Lecture, Placement> c = getModel().getCriterion(InstructorStudentHardConflict.class);
112            double hard = (c == null ? 0.0 : c.getValue(assignment, variables));
113            info.put("Instructor student conflicts", sDoubleFormat.format(conf) + (hard > 0.0 ? " [hard: " + sDoubleFormat.format(hard) + "]" : ""));
114        }
115    }
116
117}