@Test
public void testGemvDense() throws Exception {

    DenseVector y1 = DenseVector.ones(2);
    BLAS.gemv(2.0, mat, false, dv2, 0., y1);
    Assert.assertArrayEquals(new double[]{28, 64}, y1.data, TOL);
    DenseVector y2 = DenseVector.ones(2);
    BLAS.gemv(2.0, mat, false, dv2, 1., y2);
    Assert.assertArrayEquals(new double[]{29, 65}, y2.data, TOL);
}