BUG: DataFrame.from_records with empty rec array #20806
Conversation
keep the dtypes Closes pandas-dev#20805
pandas/core/frame.py
Outdated
| @@ -7387,7 +7387,10 @@ def _to_arrays(data, columns, coerce_float=False, dtype=None): | |||
| if isinstance(data, np.ndarray): | |||
| columns = data.dtype.names | |||
| if columns is not None: | |||
| return [[]] * len(columns), columns | |||
| arrays = [np.array([], dtype=dtype) | |||
| for _, dtype in data.dtype.descr] | |||
There was a problem hiding this comment.
What's the reasoning for using the descr here instead of just the dtype? ref #20734 and the docs for dtype.descrI think we may run into some obscure issues using the str representation of the type instead of the type directly
| assert df.index.name == 'id' | ||
|
|
||
| def test_from_records_empty_dtypes(self): |
There was a problem hiding this comment.
Think we should cover more dtypes? Perhaps a good use case for a shared fixture?
There was a problem hiding this comment.
can you add some more here?
|
@WillAyd comments, and a lint issue. otherwise lgtm. |
Codecov Report
@@ Coverage Diff @@
## master #20806 +/- ##
==========================================
+ Coverage 91.81% 91.83% +0.02%
==========================================
Files 153 153
Lines 49318 49319 +1
==========================================
+ Hits 45279 45294 +15
+ Misses 4039 4025 -14
Continue to review full report at Codecov.
|
|
Hmm I can't reproduce the failures locally with those versions of python / NumPy. May end up pushing this. The |
| @@ -1092,6 +1092,7 @@ Numeric | |||
| - Bug in :class:`Series` constructor with an int or float list where specifying ``dtype=str``, ``dtype='str'`` or ``dtype='U'`` failed to convert the data elements to strings (:issue:`16605`) | |||
| - Bug in :class:`Index` multiplication and division methods where operating with a ``Series`` would return an ``Index`` object instead of a ``Series`` object (:issue:`19042`) | |||
| - Bug in the :class:`DataFrame` constructor in which data containing very large positive or very large negative numbers was causing ``OverflowError`` (:issue:`18584`) | |||
| - Bug in the :meth:`DataFrame.from_records` constructor losing the dtypes of a empty NumPy record array (:issue:`20805`) | |||
| assert df.index.name == 'id' | ||
|
|
||
| def test_from_records_empty_dtypes(self): |
There was a problem hiding this comment.
can you add some more here?
|
can you rebase |
|
closing as stale. if you'd like to continue, pls ping. |
keep the dtypes
Closes #20805