@Test
public void split() throws Exception {

    BatchOperator data = Iris.getBatchData();
    data = new AppendIdBatchOp().linkFrom(data);
    BatchOperator spliter = new SplitBatchOp().setFraction(0.1);
    BatchOperator left = spliter.linkFrom(data);
    BatchOperator right = spliter.getSideOutput(0);
    Assert.assertEquals(left.count(), 15);
    Assert.assertEquals(right.count(), 150 - 15);
    Assert.assertEquals(new UnionBatchOp().linkFrom(left, right).count(), 150);
}