Ejemplo n.º 1
0
  protected int NN(int nSel, double conj[][], double ejemplo[]) {
    double mindist, dist;
    int nneigh = -1;

    mindist = Double.POSITIVE_INFINITY;

    for (int i = 0; i < nSel; i++) {
      dist = KNN.distancia(conj[i], ejemplo);
      if (dist < mindist) {
        mindist = dist;
        nneigh = i;
      }
    }
    return nneigh;
  }
Ejemplo n.º 2
0
  int nextNeighbour(boolean marcas[], double datos[][], int ej, Vector<Integer> vecinos) {

    int i, j, k;
    int pos = -1;
    double distmin = Double.POSITIVE_INFINITY;
    double distancia;
    double centroid[];
    double prototipo[];

    /*Computation of the previous centroid*/
    centroid = new double[datos[0].length];
    prototipo = new double[datos[0].length];

    for (j = 0; j < datos[0].length; j++) {
      centroid[j] = 0;
      for (k = 0; k < vecinos.size(); k++) {
        centroid[j] += datos[vecinos.elementAt(k).intValue()][j];
      }
    }

    for (i = 0; i < datos.length; i++) {
      if (marcas[i] && i != ej) {
        for (j = 0; j < datos[0].length; j++) {
          prototipo[j] = centroid[j] + datos[i][j];
          prototipo[j] /= (vecinos.size() + 1);
        }
        distancia = KNN.distancia(datos[ej], prototipo);
        if (distancia < distmin) {
          distmin = distancia;
          pos = i;
        }
      }
    }

    return pos;
  }
Ejemplo n.º 3
0
  /**
   * The main method of the class that includes the operations of the algorithm. It includes all the
   * operations that the algorithm has and finishes when it writes the output information into
   * files.
   */
  public void run() {

    int S[];
    int i, j, l, m;
    int nPos = 0, nNeg = 0;
    int posID;
    int nClases;
    int pos;
    int baraje[];
    int tmp;
    double conjS[][];
    int clasesS[];
    int tamS = 0;
    int claseObt;
    int cont;
    int busq;
    boolean marcas[];
    int nSel;
    double conjS2[][];
    int clasesS2[];
    double minDist, dist;

    long tiempo = System.currentTimeMillis();

    /*CNN PART*/

    /*Count of number of positive and negative examples*/
    for (i = 0; i < clasesTrain.length; i++) {
      if (clasesTrain[i] == 0) nPos++;
      else nNeg++;
    }
    if (nPos > nNeg) {
      tmp = nPos;
      nPos = nNeg;
      nNeg = tmp;
      posID = 1;
    } else {
      posID = 0;
    }

    /*Inicialization of the candidates set*/
    S = new int[datosTrain.length];
    for (i = 0; i < S.length; i++) S[i] = Integer.MAX_VALUE;

    /*Inserting an element of mayority class*/
    Randomize.setSeed(semilla);
    pos = Randomize.Randint(0, clasesTrain.length - 1);
    while (clasesTrain[pos] == posID) pos = (pos + 1) % clasesTrain.length;
    S[tamS] = pos;
    tamS++;

    /*Insert all subset of minority class*/
    for (i = 0; i < clasesTrain.length; i++) {
      if (clasesTrain[i] == posID) {
        S[tamS] = i;
        tamS++;
      }
    }

    /*Algorithm body. We resort randomly the instances of T and compare with the rest of S.
    If an instance doesn´t classified correctly, it is inserted in S*/
    baraje = new int[datosTrain.length];
    for (i = 0; i < datosTrain.length; i++) baraje[i] = i;
    for (i = 0; i < datosTrain.length; i++) {
      pos = Randomize.Randint(i, clasesTrain.length - 1);
      tmp = baraje[i];
      baraje[i] = baraje[pos];
      baraje[pos] = tmp;
    }

    for (i = 0; i < datosTrain.length; i++) {
      if (clasesTrain[i] != posID) { // only for mayority class instances
        /*Construction of the S set from the previous vector S*/
        conjS = new double[tamS][datosTrain[0].length];
        clasesS = new int[tamS];
        for (j = 0; j < tamS; j++) {
          for (l = 0; l < datosTrain[0].length; l++) conjS[j][l] = datosTrain[S[j]][l];
          clasesS[j] = clasesTrain[S[j]];
        }

        /*Do KNN to the instance*/
        claseObt = KNN.evaluacionKNN(k, conjS, clasesS, datosTrain[baraje[i]], 2);
        if (claseObt != clasesTrain[baraje[i]]) { // fail in the class, it is included in S
          Arrays.sort(S);
          busq = Arrays.binarySearch(S, baraje[i]);
          if (busq < 0) {
            S[tamS] = baraje[i];
            tamS++;
          }
        }
      }
    }

    /*Construction of the S set from the previous vector S*/
    conjS = new double[tamS][datosTrain[0].length];
    clasesS = new int[tamS];
    for (j = 0; j < tamS; j++) {
      for (l = 0; l < datosTrain[0].length; l++) conjS[j][l] = datosTrain[S[j]][l];
      clasesS[j] = clasesTrain[S[j]];
    }

    /*TOMEK LINKS PART*/

    /*Inicialization of the instance flagged vector of the S set*/
    marcas = new boolean[conjS.length];
    for (i = 0; i < conjS.length; i++) {
      marcas[i] = true;
    }
    nSel = conjS.length;

    for (i = 0; i < conjS.length; i++) {
      minDist = Double.POSITIVE_INFINITY;
      pos = 0;
      for (j = 0; j < conjS.length; j++) {
        if (i != j) {
          dist = KNN.distancia(conjS[i], conjS[j]);
          if (dist < minDist) {
            minDist = dist;
            pos = j;
          }
        }
      }
      if (clasesS[i] != clasesS[pos]) {
        if (clasesS[i] != posID) {
          if (marcas[i] == true) {
            marcas[i] = false;
            nSel--;
          }
        } else {
          if (marcas[pos] == true) {
            marcas[pos] = false;
            nSel--;
          }
        }
      }
    }

    /*Construction of the S set from the flags*/
    conjS2 = new double[nSel][conjS[0].length];
    clasesS2 = new int[nSel];
    for (m = 0, l = 0; m < conjS.length; m++) {
      if (marcas[m]) { // the instance will evaluate
        for (j = 0; j < conjS[0].length; j++) {
          conjS2[l][j] = conjS[m][j];
        }
        clasesS2[l] = clasesS[m];
        l++;
      }
    }

    System.out.println(
        "CNN_TomekLinks "
            + relation
            + " "
            + (double) (System.currentTimeMillis() - tiempo) / 1000.0
            + "s");

    OutputIS.escribeSalida(
        ficheroSalida[0], conjS2, clasesS2, entradas, salida, nEntradas, relation);
    OutputIS.escribeSalida(ficheroSalida[1], test, entradas, salida, nEntradas, relation);
  }
Ejemplo n.º 4
0
  /**
   * Evaluates a chromosome
   *
   * @param datos Reference to the training set
   * @param real Reference to the training set (real valued)
   * @param nominal Reference to the training set (nominal valued)
   * @param nulos Reference to the training set (null values)
   * @param clases Output attribute of each instance
   * @param alfa Alpha value of the fitness function
   * @param kNeigh Number of neighbors for the KNN algorithm
   * @param nClases Number of classes of the problem
   * @param distanceEu True= Euclidean distance; False= HVDM
   */
  public void evalua(
      double datos[][],
      double real[][],
      int nominal[][],
      boolean nulos[][],
      int clases[],
      double alfa,
      int kNeigh,
      int nClases,
      boolean distanceEu) {

    int i, j, l, m;
    int aciertos = 0;
    double M, s;
    double conjS[][];
    double conjR[][];
    int conjN[][];
    boolean conjM[][];
    int clasesS[];
    int vecinos[];
    int claseObt;
    int vecinoCercano;
    double dist, minDist;

    M = (double) datos.length;
    s = (double) genesActivos();

    if (kNeigh > 1) {
      vecinos = new int[kNeigh];
      conjS = new double[(int) s][datos[0].length];
      conjR = new double[(int) s][datos[0].length];
      conjN = new int[(int) s][datos[0].length];
      conjM = new boolean[(int) s][datos[0].length];
      clasesS = new int[(int) s];
      for (j = 0, l = 0; j < datos.length; j++) {
        if (cuerpo[j]) { // the instance must be copied to the solution
          for (m = 0; m < datos[j].length; m++) {
            conjS[l][m] = datos[j][m];
            conjR[l][m] = real[j][m];
            conjN[l][m] = nominal[j][m];
            conjM[l][m] = nulos[j][m];
          }
          clasesS[l] = clases[j];
          l++;
        }
      }

      for (i = 0; i < datos.length; i++) {
        claseObt =
            KNN.evaluacionKNN2(
                kNeigh,
                conjS,
                conjR,
                conjN,
                conjM,
                clasesS,
                datos[i],
                real[i],
                nominal[i],
                nulos[i],
                nClases,
                distanceEu,
                vecinos);
        if (claseObt >= 0) if (clases[i] == claseObt) aciertos++;
      }
    } else {
      for (i = 0; i < datos.length; i++) {
        vecinoCercano = -1;
        minDist = Double.POSITIVE_INFINITY;
        for (j = 0; j < datos.length; j++) {
          if (cuerpo[j]) { // It is in S
            dist =
                KNN.distancia(
                    datos[i],
                    real[i],
                    nominal[i],
                    nulos[i],
                    datos[j],
                    real[j],
                    nominal[j],
                    nulos[j],
                    distanceEu);
            if (dist < minDist && dist != 0) {
              minDist = dist;
              vecinoCercano = j;
            }
          }
        }
        if (vecinoCercano >= 0) if (clases[i] == clases[vecinoCercano]) aciertos++;
      }
    }

    calidad = ((double) (aciertos) / M) * alfa * 100.0;
    calidad += ((1.0 - alfa) * 100.0 * (M - s) / M);
    cruzado = false;
  } // end-method