/** * Computes the distance between two instances (without previous normalization) * * @param i First instance * @param j Second instance * @return The Euclidean distance between i and j */ private double distance(Instance i, Instance j) { double dist = 0; int in = 0; int out = 0; for (int l = 0; l < nvariables; l++) { Attribute a = Attributes.getAttribute(l); direccion = a.getDirectionAttribute(); tipo = a.getType(); if (direccion == Attribute.INPUT) { if (tipo != Attribute.NOMINAL && !i.getInputMissingValues(in)) { // real value, apply euclidean distance dist += (i.getInputRealValues(in) - j.getInputRealValues(in)) * (i.getInputRealValues(in) - j.getInputRealValues(in)); } else { if (!i.getInputMissingValues(in) && i.getInputNominalValues(in) != j.getInputNominalValues(in)) dist += 1; } in++; } else { if (direccion == Attribute.OUTPUT) { if (tipo != Attribute.NOMINAL && !i.getOutputMissingValues(out)) { dist += (i.getOutputRealValues(out) - j.getOutputRealValues(out)) * (i.getOutputRealValues(out) - j.getOutputRealValues(out)); } else { if (!i.getOutputMissingValues(out) && i.getOutputNominalValues(out) != j.getOutputNominalValues(out)) dist += 1; } out++; } } } return dist; }
/** Process the training and test files provided in the parameters file to the constructor. */ public void process() { // declarations double[] outputs; double[] outputs2; Instance neighbor; double dist, mean; int actual; Randomize rnd = new Randomize(); Instance ex; gCenter kmeans = null; int iterations = 0; double E; double prevE; int totalMissing = 0; boolean allMissing = true; rnd.setSeed(semilla); // PROCESS try { // Load in memory a dataset that contains a classification problem IS.readSet(input_train_name, true); int in = 0; int out = 0; ndatos = IS.getNumInstances(); nvariables = Attributes.getNumAttributes(); nentradas = Attributes.getInputNumAttributes(); nsalidas = Attributes.getOutputNumAttributes(); X = new String[ndatos][nvariables]; // matrix with transformed data kmeans = new gCenter(K, ndatos, nvariables); timesSeen = new FreqList[nvariables]; mostCommon = new String[nvariables]; // first, we choose k 'means' randomly from all // instances totalMissing = 0; for (int i = 0; i < ndatos; i++) { Instance inst = IS.getInstance(i); if (inst.existsAnyMissingValue()) totalMissing++; } if (totalMissing == ndatos) allMissing = true; else allMissing = false; for (int numMeans = 0; numMeans < K; numMeans++) { do { actual = (int) (ndatos * rnd.Rand()); ex = IS.getInstance(actual); } while (ex.existsAnyMissingValue() && !allMissing); kmeans.copyCenter(ex, numMeans); } // now, iterate adjusting clusters' centers and // instances to them prevE = 0; iterations = 0; do { for (int i = 0; i < ndatos; i++) { Instance inst = IS.getInstance(i); kmeans.setClusterOf(inst, i); } // set new centers kmeans.recalculateCenters(IS); // compute RMSE E = 0; for (int i = 0; i < ndatos; i++) { Instance inst = IS.getInstance(i); E += kmeans.distance(inst, kmeans.getClusterOf(i)); } iterations++; // System.out.println(iterations+"\t"+E); if (Math.abs(prevE - E) == 0) iterations = maxIter; else prevE = E; } while (E > minError && iterations < maxIter); for (int i = 0; i < ndatos; i++) { Instance inst = IS.getInstance(i); in = 0; out = 0; for (int j = 0; j < nvariables; j++) { Attribute a = Attributes.getAttribute(j); direccion = a.getDirectionAttribute(); tipo = a.getType(); if (direccion == Attribute.INPUT) { if (tipo != Attribute.NOMINAL && !inst.getInputMissingValues(in)) { X[i][j] = new String(String.valueOf(inst.getInputRealValues(in))); } else { if (!inst.getInputMissingValues(in)) X[i][j] = inst.getInputNominalValues(in); else { actual = kmeans.getClusterOf(i); X[i][j] = new String(kmeans.valueAt(actual, j)); } } in++; } else { if (direccion == Attribute.OUTPUT) { if (tipo != Attribute.NOMINAL && !inst.getOutputMissingValues(out)) { X[i][j] = new String(String.valueOf(inst.getOutputRealValues(out))); } else { if (!inst.getOutputMissingValues(out)) X[i][j] = inst.getOutputNominalValues(out); else { actual = kmeans.getClusterOf(i); X[i][j] = new String(kmeans.valueAt(actual, j)); } } out++; } } } } } catch (Exception e) { System.out.println("Dataset exception = " + e); e.printStackTrace(); System.exit(-1); } write_results(output_train_name); /** ************************************************************************************ */ // does a test file associated exist? if (input_train_name.compareTo(input_test_name) != 0) { try { // Load in memory a dataset that contains a classification problem IStest.readSet(input_test_name, false); int in = 0; int out = 0; ndatos = IStest.getNumInstances(); nvariables = Attributes.getNumAttributes(); nentradas = Attributes.getInputNumAttributes(); nsalidas = Attributes.getOutputNumAttributes(); for (int i = 0; i < ndatos; i++) { Instance inst = IStest.getInstance(i); in = 0; out = 0; for (int j = 0; j < nvariables; j++) { Attribute a = Attributes.getAttribute(j); direccion = a.getDirectionAttribute(); tipo = a.getType(); if (direccion == Attribute.INPUT) { if (tipo != Attribute.NOMINAL && !inst.getInputMissingValues(in)) { X[i][j] = new String(String.valueOf(inst.getInputRealValues(in))); } else { if (!inst.getInputMissingValues(in)) X[i][j] = inst.getInputNominalValues(in); else { actual = kmeans.getClusterOf(i); X[i][j] = new String(kmeans.valueAt(actual, j)); } } in++; } else { if (direccion == Attribute.OUTPUT) { if (tipo != Attribute.NOMINAL && !inst.getOutputMissingValues(out)) { X[i][j] = new String(String.valueOf(inst.getOutputRealValues(out))); } else { if (!inst.getOutputMissingValues(out)) X[i][j] = inst.getOutputNominalValues(out); else { actual = kmeans.getClusterOf(i); X[i][j] = new String(kmeans.valueAt(actual, j)); } } out++; } } } } } catch (Exception e) { System.out.println("Dataset exception = " + e); e.printStackTrace(); System.exit(-1); } write_results(output_test_name); } }