@Test
public void testAxpy() throws Exception {

    DenseVector v = DenseVector.ones(2);
    BLAS.axpy(1.0, dv1, v);
    Assert.assertArrayEquals(v.getData(), new double[]{2, 3}, TOL);
    BLAS.axpy(1.0, spv1, v);
    Assert.assertArrayEquals(v.getData(), new double[]{3, 5}, TOL);
    BLAS.axpy(1, 1.0, new double[]{1}, 0, v.getData(), 1);
    Assert.assertArrayEquals(v.getData(), new double[]{3, 6}, TOL);
}