import org.jblas.*; public class JBLASExample { public static void main(String[] args) { DoubleMatrix matrix = new DoubleMatrix(new double[][]{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}); DoubleMatrix vector = new DoubleMatrix(new double[]{1, 2, 3}); DoubleMatrix result = matrix.mmul(vector); System.out.println(result); } }