import org.apache.mahout.math.DenseMatrix; import org.apache.mahout.math.Matrix; import org.apache.mahout.math.Vector; import org.apache.mahout.math.stats.OnlineSummarizer; import org.apache.mahout.math.stats.OnlineSummarizerFactory; public class MahoutMathExample { public static void main(String[] args) { Matrix matrix = new DenseMatrix(3, 3); matrix.set(0, 0, 1); matrix.set(0, 1, 2); matrix.set(1, 1, 3); matrix.set(1, 2, 4); matrix.set(2, 2, 5); Matrix result = matrix.times(matrix); System.out.println(result); Vector vector1 = result.viewRow(0); Vector vector2 = result.viewRow(1); Vector sum = vector1.plus(vector2); System.out.println(sum); OnlineSummarizer summarizer = OnlineSummarizerFactory.create(); summarizer.add(1); summarizer.add(2); summarizer.add(3); System.out.println("Mean: " + summarizer.getMean()); System.out.println("Variance: " + summarizer.getVariance()); } }