@Test
public void testPlusEquals() throws Exception {

    DenseMatrix matA = new DenseMatrix(new double[][]{
        new double[]{1, 3, 5},
        new double[]{2, 4, 6},
    });
    DenseMatrix matB = DenseMatrix.ones(2, 3);
    matA.plusEquals(matB);
    Assert.assertArrayEquals(matA.getData(), new double[]{2, 3, 4, 5, 6, 7}, TOL);
    matA.plusEquals(1.0);
    Assert.assertArrayEquals(matA.getData(), new double[]{3, 4, 5, 6, 7, 8}, TOL);
}