@Override
public void map(Key key) {
_rows = new long[_clusters.length];
_dist = new double[_clusters.length];
assert key.home();
ValueArray va = DKV.get(_arykey).get();
AutoBuffer bits = va.getChunk(key);
int rows = va.rpc(ValueArray.getChunkIndex(key));
double[] values = new double[_cols.length - 1];
ClusterDist cd = new ClusterDist();
for (int row = 0; row < rows; row++) {
KMeans.datad(va, bits, row, _cols, _normalized, values);
KMeans.closest(_clusters, values, cd);
_rows[cd._cluster]++;
_dist[cd._cluster] += cd._dist;
}
_arykey = null;
_cols = null;
_clusters = null;
}
@Override
protected double cluster(
DataSet dataSet,
List<Double> accelCache,
int k,
List<Vec> means,
int[] assignment,
boolean exactTotal,
ExecutorService threadpool,
boolean returnError) {
return kmeans.cluster(
dataSet, accelCache, k, means, assignment, exactTotal, threadpool, returnError);
}
static ArrayList run(int para) {
modshogun.init_shogun_with_defaults();
int k = para;
init_random(17);
DoubleMatrix fm_train = Load.load_numbers("../data/fm_train_real.dat");
RealFeatures feats_train = new RealFeatures(fm_train);
EuclidianDistance distance = new EuclidianDistance(feats_train, feats_train);
KMeans kmeans = new KMeans(k, distance);
kmeans.train();
DoubleMatrix out_centers = kmeans.get_cluster_centers();
kmeans.get_radiuses();
ArrayList result = new ArrayList();
result.add(kmeans);
result.add(out_centers);
modshogun.exit_shogun();
return result;
}
/**
* Single row scoring, on properly ordered data. Will return NaN if any data element contains a
* NaN. Returns the cluster-number, which is mostly an internal value. Last data element refers to
* the response variable, which is not used for k-means.
*/
@Override
protected double score0(double[] data) {
for (int i = 0; i < data.length - 1; i++) { // Normalize the data before scoring
ValueArray.Column C = _va._cols[i];
double d = data[i];
if (_normalized) {
d -= C._mean;
if (C._sigma != 0.0 && !Double.isNaN(C._sigma)) d /= C._sigma;
}
data[i] = d;
}
data[data.length - 1] = Double.NaN; // Response variable column not used
return KMeans.closest(_clusters, data, new ClusterDist())._cluster;
}
/**
* Creates a new ValueArray with classes. New ValueArray is not aligned with source one
* unfortunately so have to send results to each chunk owner using Atomic.
*/
@Override
public void map(Key key) {
assert key.home();
if (Job.isRunning(_job.self())) {
ValueArray va = DKV.get(_arykey).get();
AutoBuffer bits = va.getChunk(key);
long startRow = va.startRow(ValueArray.getChunkIndex(key));
int rows = va.rpc(ValueArray.getChunkIndex(key));
int rpc = (int) (ValueArray.CHUNK_SZ / ROW_SIZE);
long chunk = ValueArray.chknum(startRow, va.numRows(), ROW_SIZE);
long updatedChk = chunk;
long updatedRow = startRow;
double[] values = new double[_cols.length - 1];
ClusterDist cd = new ClusterDist();
int[] clusters = new int[rows];
int count = 0;
for (int row = 0; row < rows; row++) {
KMeans.datad(va, bits, row, _cols, _normalized, values);
KMeans.closest(_clusters, values, cd);
chunk = ValueArray.chknum(startRow + row, va.numRows(), ROW_SIZE);
if (chunk != updatedChk) {
updateClusters(clusters, count, updatedChk, va.numRows(), rpc, updatedRow);
updatedChk = chunk;
updatedRow = startRow + row;
count = 0;
}
clusters[count++] = cd._cluster;
}
if (count > 0) updateClusters(clusters, count, chunk, va.numRows(), rpc, updatedRow);
_job.updateProgress(1);
}
_job = null;
_arykey = null;
_cols = null;
_clusters = null;
}
/**
* This method implements the clustering-based misclassified sample exploitation technique. In
* this method we sample around each of the clusters by creating queries such as the following:
* SELECT rowc, colc FROM testing WHERE (rowc >= 662.5 AND rowc <= 702.5 AND colc >= 992 AND colc
* <= 1053 )
*
* @param numberOfClusters the number of clusters to be explored.
* @return an arrayList containing the samples that we have selected from the misclassified
* sampling areas
* @throws Exception
*/
@Override
public ArrayList<Tuple> getNearestMissclassified(
int numberOfClusters, ArrayList<Tuple> misclassified) throws Exception {
Statement statement;
ResultSet rs;
ArrayList<Tuple> rand = new ArrayList<Tuple>();
double percenAroundMiscl = Global.PERCENT_AROUND_MISCLASSIFIED;
KMeans k = new KMeans();
ArrayList<Tuple> centroids = k.getCentroids(numberOfClusters);
int[] assignments = null;
if (k.centroidsExist == true) {
assignments = k.assignments;
}
System.out.println(
"Exploring the clusters of misclassified. Number of clusters: " + numberOfClusters);
// total number of tuples we should spend on the misclassified phase.
for (int im = 0; im < centroids.size(); im++) {
// System.out.println("This is the centroid: "+centroids.get(0));
ArrayList<Tuple> h = new ArrayList<Tuple>();
Tuple t = centroids.get(im);
String query = "SELECT " + Global.OBJECT_KEY + " , ";
for (int i = 0; i < Global.attributes.size(); i++) {
if (i != Global.attributes.size() - 1) query += Global.attributes.get(i).getName() + " , ";
else query += Global.attributes.get(i).getName();
}
query += " FROM " + Global.TABLE_NAME + " WHERE ";
for (int i = 0; i < Global.attributes.size(); i++) {
ArrayList<String> valuesForQuery =
getClosest(
Global.attributes.get(i).getDomain(), percenAroundMiscl, (double) t.valueAt(i));
if (k.centroidsExist == true) {
while (checkOK(misclassified, valuesForQuery, assignments, im, i) == false) {
percenAroundMiscl++;
valuesForQuery =
getClosest(
Global.attributes.get(i).getDomain(), percenAroundMiscl, (double) t.valueAt(i));
}
}
query +=
" ("
+ Global.attributes.get(i).getName()
+ " >= "
+ valuesForQuery.get(0)
+ " AND "
+ Global.attributes.get(i).getName()
+ " <= "
+ valuesForQuery.get(1)
+ ") ";
if (i < Global.attributes.size() - 1) {
query += " AND ";
}
}
query += " ORDER BY RANDOM() LIMIT " + Global.RANDOM_AROUND_MISCLASSIFIED;
Connection connection = DBConnection.getConnection();
statement =
connection.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_READ_ONLY);
rs = statement.executeQuery(query);
while (rs.next()) {
Object key = rs.getString(1);
Object[] attrValues = new Object[Global.attributes.size()];
for (int m = 1; m <= Global.attributes.size(); m++) {
attrValues[m - 1] = rs.getString(m + 1);
}
Tuple tuple = new Tuple(key, attrValues);
h.add(tuple);
}
rand.addAll(h);
}
return rand; // returns an ArrayList with the k nearest neighbors
}
