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Python 2.7.11 (default, Dec 15 2015, 16:46:19) 
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In [1]: import dask.array as da

In [2]: x = da.fromfunction(lambda i, j, k: i + j + k**2, chunks=(5, 512, 512), shape=(100, 2048, 2048), dtype='f8')

In [3]: x.to_hdf5('myfile.hdf5', '/x', compression='lzf', shuffle=True)

In [4]: import h5py

In [5]: f = h5py.File('myfile.hdf5')

In [6]: dset = f['/x']

In [7]: dset
Out[7]: <HDF5 dataset "x": shape (100, 2048, 2048), type "<f8">

In [8]: dset.chunks
Out[8]: (5, 512, 512)

In [9]: import dask.array as da

In [10]: x = da.from_array(dset, chunks=(5, 512, 512))

In [11]: x
Out[11]: dask.array<from-ar..., shape=(100, 2048, 2048), dtype=float64, chunksize=(5, 512, 512)>

In [12]: a = x[0, :5, :5]

In [13]: b = x[:, :5, :5]

In [14]: c = a - b.mean()

In [15]: c.compute()
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-15-0c5d552d1b01> in <module>()
----> 1 c.compute()

/usr/local/lib/python2.7/dist-packages/dask/base.pyc in compute(self, **kwargs)
     32 
     33     def compute(self, **kwargs):
---> 34         return compute(self, **kwargs)[0]
     35 
     36     @classmethod

/usr/local/lib/python2.7/dist-packages/dask/base.pyc in compute(*args, **kwargs)
    100                 for opt, val in groups.items()])
    101     keys = [arg._keys() for arg in args]
--> 102     results = get(dsk, keys, **kwargs)
    103     return tuple(a._finalize(a, r) for a, r in zip(args, results))
    104 

/usr/local/lib/python2.7/dist-packages/dask/threaded.pyc in get(dsk, result, cache, num_workers, **kwargs)
     55     results = get_async(pool.apply_async, len(pool._pool), dsk, result,
     56                         cache=cache, queue=queue, get_id=_thread_get_id,
---> 57                         **kwargs)
     58 
     59     return results

/usr/local/lib/python2.7/dist-packages/dask/async.pyc in get_async(apply_async, num_workers, dsk, result, cache, queue, get_id, raise_on_exception, rerun_exceptions_locally, callbacks, **kwargs)
    481                 _execute_task(task, data)  # Re-execute locally
    482             else:
--> 483                 raise(remote_exception(res, tb))
    484         state['cache'][key] = res
    485         finish_task(dsk, key, state, results, keyorder.get)

AttributeError: 'thread._local' object has no attribute 'astype'

Traceback
---------
  File "/usr/local/lib/python2.7/dist-packages/dask/async.py", line 263, in execute_task
    result = _execute_task(task, data)
  File "/usr/local/lib/python2.7/dist-packages/dask/async.py", line 244, in _execute_task
    args2 = [_execute_task(a, cache) for a in args]
  File "/usr/local/lib/python2.7/dist-packages/dask/async.py", line 245, in _execute_task
    return func(*args2)
  File "/usr/local/lib/python2.7/dist-packages/dask/array/core.py", line 48, in getarray
    c = a[b]
  File "/usr/lib/python2.7/dist-packages/h5py/_hl/dataset.py", line 367, in __getitem__
    if self._local.astype is not None: