dictionary.java

Create a problem solver for linear programming

/*
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 * and open the template in the editor.
 */

package ro.simplex;

import java.util.ArrayList;
import ro.utils.Fraction;

/**
 *
 * @author Doan Chien Thang
 */
public class Dictionary {
    private Objective objective;
    private ArrayList<VariableConstraint> varConstraints;

    public Dictionary() {
        this.objective = new Objective();
        this.varConstraints = new ArrayList<VariableConstraint>();
    }

    public Dictionary (Objective objective,
            ArrayList<VariableConstraint> varConstraints) {
        this.objective = objective;
        this.varConstraints = varConstraints;
    }
    
    @Override
    public String toString() {
        String result = "<p><b>Le dictionnaire du problème:</b></p><br />";
        result += "<div style=\"background-color:#EDEDED;padding:10;" +
                "margin-right:15\">";
        if (!this.objective.isAuxiliary())
            result += "<b>L'objectif: z = " + objective.getObjectiveValue();
        else
            result += "<b>L'objectif: v = " + objective.getObjectiveValue();
        for (int i = 0; i < objective.getVars().size(); i++) {
            if (objective.getCoefs().get(i).isNegative()) {
                result += " - ";
                if (!objective.getCoefs().get(i).absolute().equals(new Fraction(1)))
                     result += objective.getCoefs().get(i).absolute().toString();
                result += objective.getVars().get(i).toString();
            }
            else if (!objective.getCoefs().get(i).equals(new Fraction(0, 1))) {
                result += " + ";
                if (!objective.getCoefs().get(i).absolute().equals(new Fraction(1)))
                     result += objective.getCoefs().get(i).absolute().toString();
                result += objective.getVars().get(i).toString();
            }
        }
        result += "</b><br />";
        for (int i = 0; i < varConstraints.size(); i++)
            result += "&nbsp;&nbsp;&nbsp;&nbsp;" +
                    varConstraints.get(i).toString() + "<br />";
        return result + "</div>";
    }

    private VariableConstraint getVarConstraint(Variable inVar) {
        for (int i = 0; i < this.varConstraints.size(); i++)
            if (this.varConstraints.get(i).getLeftVar().equals(inVar))
                return this.varConstraints.get(i);
        return null;
    }

    public Dictionary getNewDictionaryByChangeVariableRoles(Variable inVar,
            Variable outVar) {
        Objective newObjective = new Objective();
        ArrayList<VariableConstraint> newVarConstraints = 
                new ArrayList<VariableConstraint>();
        VariableConstraint inOutConstraint = this.getVarConstraint(inVar);
        for (int i = 0; i < varConstraints.size(); i++)
            newVarConstraints.add(varConstraints.get(i).getNewVarConstraint(
                    inVar, outVar, inOutConstraint));
        newObjective = this.objective.getNewObjective(inVar, outVar,
                inOutConstraint);
        return new Dictionary(newObjective, newVarConstraints);
    }

    public ArrayList<VariableConstraint> getVarConstraints() {
        return this.varConstraints;
    }

    public Objective getObjective() {
        return this.objective;
    }

    public void setObjective(Objective objective) {
        this.objective = objective;
    }

    public String drawTable() {
        String result = "<p><b>Le table: </b></p><br />";
        result += "<div style=\"background-color:#EDEDED;padding:10;" +
                "margin-right:15;\"><table cellpadding=\"20\">";
        result += "<tr><td>z</td>";
        for (int i = 0; i < this.objective.getVars().size(); i++)
            result += "<td>" + this.objective.getVars().get(i).toString() + "</td>";
        result += "<td>1</td><td>&nbsp;</td></tr>";
        result += "<tr><td>1</td>";
        for (int i = 0; i < this.objective.getVars().size(); i++)
            result += "<td>" + this.objective.getCoefs().get(i).getOpposite() + "</td>";
        result += "<td>" + this.objective.getObjectiveValue() + "</td>";
        result += "<td>z" + "</td></tr>";
        for (int i = 0; i < this.varConstraints.size(); i++) {
            result += "<tr><td>0</td>";
            VariableConstraint varConstraint = this.varConstraints.get(i);
            for (int j = 0; j < this.objective.getVars().size(); j++) {
                Variable var = this.objective.getVars().get(j);
                if (var.equals(varConstraint.getLeftVar())) {
                    result += "<td>1</td>";
                }
                else {
                    Fraction coef = varConstraint.getCoef(var).getOpposite();
                    result += "<td>" + coef.toString() + "</td>";
                }
            }
            result += "<td>" + varConstraint.getValue() + "</td>";
            result += varConstraint.getLeftVar().toString() + "</td>";
            result += "</tr>";
        }
        return result + "</table></div>";
    }
}