org.apache.mahout.math.Matrix Java Examples

public static MultiLabel exhaustiveSearch(int numClasses, Matrix lossMatrix, List<Double> probabilities){
    double bestScore = Double.POSITIVE_INFINITY;
    Vector vector = new DenseVector(probabilities.size());
    for (int i=0;i<vector.size();i++){
        vector.set(i,probabilities.get(i));
    }
    List<MultiLabel> multiLabels = Enumerator.enumerate(numClasses);
    MultiLabel multiLabel = null;
    for (int j=0;j<lossMatrix.numCols();j++){
        Vector column = lossMatrix.viewColumn(j);
        double score = column.dot(vector);
        System.out.println("column "+j+", expected loss = "+score);
        if (score < bestScore){
            bestScore = score;
            multiLabel = multiLabels.get(j);
        }
    }
    return multiLabel;
}
 

public static void main(String[] args) throws Exception {
 showAuc = true;
     showConfusion = true;
     Auc collector = new Auc();
     LogisticModelParameters lmp = LogisticModelParameters.loadFrom(new File(modelFile));
     CsvRecordFactory csv = lmp.getCsvRecordFactory();
     OnlineLogisticRegression lr = lmp.createRegression();
     BufferedReader in = OnlineLogisticRegressionTest.open(inputFile);
     String line = in.readLine();
     csv.firstLine(line);
     line = in.readLine();
     PrintWriter output=new PrintWriter(new OutputStreamWriter(System.out, Charsets.UTF_8), true);
     output.println("\"target\",\"model-output\",\"log-likelihood\"");
     while (line != null) {
     	System.out.println("-----" + line);
         Vector v = new SequentialAccessSparseVector(lmp.getNumFeatures());
         int target = csv.processLine(line, v);
         double score = lr.classifyScalarNoLink(v);
         output.printf(Locale.ENGLISH, "%d,%.3f,%.6f%n", target, score, lr.logLikelihood(target, v));
        collector.add(target, score);
         line = in.readLine();
         System.out.println("I am here");
       }
     output.printf(Locale.ENGLISH, "AUC = %.2f%n", collector.auc());
     Matrix m = collector.confusion();
     output.printf(Locale.ENGLISH, "confusion: [[%.1f, %.1f], [%.1f, %.1f]]%n",
       m.get(0, 0), m.get(1, 0), m.get(0, 1), m.get(1, 1));
     m = collector.entropy();
     output.printf(Locale.ENGLISH, "entropy: [[%.1f, %.1f], [%.1f, %.1f]]%n",
       m.get(0, 0), m.get(1, 0), m.get(0, 1), m.get(1, 1));
}
 

public void writeOrigOfflineModel(Path model, FileSystem fs,
		org.apache.hadoop.conf.Configuration conf, MsgpackClient client)
		throws Exception {
	Vector alpha = readVector(new Path(model, "alpha"), fs, conf);
	Vector beta = readVector(new Path(model, "beta"), fs, conf);
	Matrix A = readMatrix(new Path(model, "A"), fs, conf);

	Object[] req = new Object[3];
	List<Float> alpha1 = new ArrayList<Float>(alpha.size());

	for (int i = 0; i < alpha.size(); i++) {
		alpha1.add((float) (alpha.get(i)));
	}
	req[0] = alpha1;

	List<Float> beta1 = new ArrayList<Float>(beta.size());
	for (int i = 0; i < beta.size(); i++) {
		beta1.add((float) beta.get(i));
	}
	req[1] = beta1;

	List<Float> conjunction = new ArrayList<Float>(A.numRows()
			* A.numCols());
	for (int row = 0; row < A.numRows(); row++) {
		Vector vec = A.viewRow(row);
		for (int col = 0; col < A.numCols(); col++) {
			conjunction.add((float) vec.get(col));
		}
	}
	req[2] = conjunction;
	client.writeIgnoreRetValue(req, "updateLaserOfflineModel");

}
 

private static void test2(){
    int numLabels = 5;
    Matrix matrix = LossMatrixGenerator.matrix(numLabels,"f1");
    List<MultiLabel> multiLabels = Enumerator.enumerate(numLabels);
    List<Double> dis = LossMatrixGenerator.sampleDistribution(numLabels);
    GeneralF1Predictor generalF1Predictor = new GeneralF1Predictor();
    generalF1Predictor.setMaxSize(3);
    MultiLabel pred = generalF1Predictor.predict(numLabels,multiLabels,dis);
    MultiLabel search = GeneralF1Predictor.exhaustiveSearch(numLabels,matrix,dis);
    System.out.println("pred = "+pred);
    System.out.println("search = "+search);



}
 

public static Matrix readMatrix(Path path, FileSystem fs, Configuration conf)
		throws IOException {
	FSDataInputStream in = fs.open(path);
	return MatrixWritable.readMatrix(in);
}
 

public static void writeMatrix(Matrix m, Path path, FileSystem fs,
		Configuration conf) throws IOException {
	FSDataOutputStream out = fs.create(path);
	MatrixWritable.writeMatrix(out, m);
	out.close();
}
 

@Override
public Matrix cross(Vector vector) {
    return null;
}
 

@Override public Matrix cross(Vector arg0) { throw new UnsupportedOperationException(); }