@Test
public void testMatrixTimesVector() throws Exception {

  Vector v = new RandomAccessSparseVector(50);
  v.assign(1.0);
  Matrix m = SolverTest.randomSequentialAccessSparseMatrix(100, 90, 50, 20, 1.0);
  DistributedRowMatrix dm = randomDistributedMatrix(100, 90, 50, 20, 1.0, false);
  Vector expected = m.times(v);
  Vector actual = dm.times(v);
  assertEquals(0.0, expected.getDistanceSquared(actual), EPSILON);
}