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https://issues.apache.org/jira/browse/ARROW-2142?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16369605#comment-16369605
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Wes McKinney commented on ARROW-2142:
-------------------------------------

It sounds like we will need to write a function that combines a sequence of 
chunked arrays into a struct, where each of the arrays possibly has a different 
chunked layout. So something like

{{NestChunkedArrays(fields, chunked_arrays, &result)}} 

(or some other such name, actually kind of hard to name this operation). The 
result would be another {{ChunkedArray}}. The implementation will be like 
https://github.com/apache/arrow/blob/master/cpp/src/arrow/table.h#L223, where 
we convert possibly chunked columns into a sequence of record batches, each of 
whose fields is non-chunked

> [Python] Conversion from Numpy struct array unimplemented
> ---------------------------------------------------------
>
>                 Key: ARROW-2142
>                 URL: https://issues.apache.org/jira/browse/ARROW-2142
>             Project: Apache Arrow
>          Issue Type: Improvement
>          Components: Python
>    Affects Versions: 0.8.0
>            Reporter: Antoine Pitrou
>            Priority: Major
>
> {code:python}
> >>> arr = np.array([(1.5,)], dtype=np.dtype([('x', np.float32)]))
> >>> arr
> array([(1.5,)], dtype=[('x', '<f4')])
> >>> arr[0]
> (1.5,)
> >>> arr['x']
> array([1.5], dtype=float32)
> >>> arr['x'][0]
> 1.5
> >>> pa.array(arr, type=pa.struct([pa.field('x', pa.float32())]))
> Traceback (most recent call last):
>   File "<ipython-input-18-27a52820b7d8>", line 1, in <module>
>     pa.array(arr, type=pa.struct([pa.field('x', pa.float32())]))
>   File "array.pxi", line 177, in pyarrow.lib.array
>   File "error.pxi", line 77, in pyarrow.lib.check_status
>   File "error.pxi", line 85, in pyarrow.lib.check_status
> ArrowNotImplementedError: 
> /home/antoine/arrow/cpp/src/arrow/python/numpy_to_arrow.cc:1585 code: 
> converter.Convert()
> NumPyConverter doesn't implement <struct<x: float>> conversion.
> {code}



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