galipremsagar commented on issue #15178:
URL: https://github.com/apache/arrow/issues/15178#issuecomment-1370198289
Worth noting that performing a `slice` operation also seems to be dropping
the index after round-trip:
```python
In [18]: df.index = pd.RangeIndex(2, 10, 2)
In [19]: table = pa.Table.from_pandas(df)
In [20]: table.schema.pandas_metadata
Out[20]:
{'index_columns': [{'kind': 'range',
'name': None,
'start': 2,
'stop': 10,
'step': 2}],
'column_indexes': [{'name': None,
'field_name': None,
'pandas_type': 'unicode',
'numpy_type': 'object',
'metadata': {'encoding': 'UTF-8'}}],
'columns': [{'name': 'n_legs',
'field_name': 'n_legs',
'pandas_type': 'int64',
'numpy_type': 'int64',
'metadata': None},
{'name': 'animals',
'field_name': 'animals',
'pandas_type': 'unicode',
'numpy_type': 'object',
'metadata': None}],
'creator': {'library': 'pyarrow', 'version': '10.0.1'},
'pandas_version': '1.5.2'}
In [21]: table.slice(0, 2)
Out[21]:
pyarrow.Table
n_legs: int64
animals: string
----
n_legs: [[2,4]]
animals: [["Flamingo","Horse"]]
In [22]: table.slice(0, 2).to_pandas()
Out[22]:
n_legs animals
0 2 Flamingo
1 4 Horse
In [23]: df
Out[23]:
n_legs animals
2 2 Flamingo
4 4 Horse
6 5 Brittle stars
8 100 Centipede
```
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