# Buggy code
def execute_tileable(
    self,
    tileable,
    n_parallel=None,
    n_thread=None,
    concat=False,
    print_progress=False,
    mock=False,
    compose=True,
):
    if concat:
        # only for tests
        tileable.tiles()
        if len(tileable.chunks) > 1:
            tileable = tileable.op.concat_tileable_chunks(tileable)

    graph = tileable.build_graph(cls=DirectedGraph, tiled=True, compose=compose)

    return self.execute_graph(
        graph,
        [c.key for c in tileable.chunks],
        n_parallel=n_parallel or n_thread,
        print_progress=print_progress,
        mock=mock,
    )


# Traceback (Exception)
In [28]: df = md.DataFrame(np.random.rand(10, 2))

In [29]: df + np.random.rand(10, 2)
---------------------------------------------------------------------------
Exception                                 Traceback (most recent call last)
<ipython-input-29-4a212df011a8> in <module>
----> 1 df + np.random.rand(10, 2)

~/Documents/mars_dev/mars/mars/dataframe/utils.py in wrapper(*args, **kwargs)
613     def wrapper(*args, **kwargs):
614         try:
--> 615             return func(*args, **kwargs)
616         except NotImplementedError:
617             return NotImplemented

~/Documents/mars_dev/mars/mars/dataframe/arithmetic/add.py in add(df, other, axis, level, fill_value)
33
34 def add(df, other, axis='columns', level=None, fill_value=None):
---> 35     other = wrap_sequence(other)
36     op = DataFrameAdd(axis=axis, level=level, fill_value=fill_value, lhs=df, rhs=other)
37     return op(df, other)

~/Documents/mars_dev/mars/mars/dataframe/utils.py in wrap_sequence(seq)
606
607     if isinstance(seq, (list, tuple, np.ndarray, TENSOR_TYPE)):
--> 608         seq = Series(seq)
609     return seq
610

~/Documents/mars_dev/mars/mars/dataframe/initializer.py in __init__(self, data, index, dtype, name, copy, chunk_size, gpu, sparse)
46             series = data
47         else:
---> 48             pd_series = pd.Series(data, index=index, dtype=dtype, name=name, copy=copy)
49             series = from_pandas_series(pd_series, chunk_size=chunk_size, gpu=gpu, sparse=sparse)
50         super(Series, self).__init__(series.data)

~/miniconda3/lib/python3.7/site-packages/pandas/core/series.py in __init__(self, data, index, dtype, name, copy, fastpath)
312                     data = data.copy()
313             else:
--> 314                 data = sanitize_array(data, index, dtype, copy, raise_cast_failure=True)
315
316                 data = SingleBlockManager(data, index, fastpath=True)

~/miniconda3/lib/python3.7/site-packages/pandas/core/internals/construction.py in sanitize_array(data, index, dtype, copy, raise_cast_failure)
727     elif subarr.ndim > 1:
728         if isinstance(data, np.ndarray):
--> 729             raise Exception("Data must be 1-dimensional")
730         else:
731             subarr = com.asarray_tuplesafe(data, dtype=dtype)

Exception: Data must be 1-dimensional

# Fixed code
def execute_tileable(
    self,
    tileable,
    n_parallel=None,
    n_thread=None,
    concat=False,
    print_progress=False,
    mock=False,
    compose=True,
):
    if concat:
        # only for tests
        tileable.tiles()
        if len(tileable.chunks) > 1:
            tileable = tileable.op.concat_tileable_chunks(tileable)

    # shallow copy
    chunk_result = self._chunk_result.copy()
    graph = tileable.build_graph(cls=DirectedGraph, tiled=True, compose=compose)
    ret = self.execute_graph(
        graph,
        [c.key for c in tileable.chunks],
        n_parallel=n_parallel or n_thread,
        print_progress=print_progress,
        mock=mock,
        chunk_result=chunk_result,
    )
    self._chunk_result.update(chunk_result)
    return ret