Preserve DataFrame(columns=).columns dtype during empty-like construction #14381
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mroeschke
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bug
wence-
approved these changes
Nov 14, 2023
python/cudf/cudf/core/dataframe.py
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| if len(columns) == 0: | ||
| empty_dtype = getattr(columns, "dtype", None) | ||
| else: | ||
| empty_dtype = None |
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If the columns are non-empty and have a dtype, should we respect that? It feels like there are still times in which we might lose the dtype, or do I have it wrong?
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Good point. Currently a column passed in as int8 would be returned as int64. I'll push an update to avoid this upcasting
|
In a followup, I have a feeling |
…me/empty_column_type
…me/empty_column_type
wence-
approved these changes
Nov 21, 2023
|
/merge |
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Description
.columnused to always returnpd.Index([], dtype=object)even if an empty-dtyped columns was passed into the DataFrame constructor e.g.DatetimeIndex([]). Needed to preserved some information about what column dtype was passed in so we can return a correctly type IndexChecklist