[ARROW-14004] [Python] to_pandas() converts to float instead of using pandas nullable types

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 6.0.0
• Component/s: Documentation, Python
• Labels: pandas pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/29604
• Assignee: Joris Van den Bossche
• Reporter: Miguel Cantón Cortés
• Created: 15/Sep/21 14:45
• Updated: 11/Jan/23 08:36
• Resolved: 20/Oct/21 12:39

Description

We've noticed that when converting an Arrow Table to pandas using `.to_pandas()` integer columns with null values get converted to float instead of using pandas nullable types.

If the column was created with pandas first it is correctly preserved (I guess it's using stored metadata for this).

I've attached a screenshot showing this behavior.

As currently there is support for nullable types in pandas, just as in Arrow, it would be great to use these types when dealing with columns with null values.

If you are reticent to change this behavior, a param would be nice too (e.g. `to_pandas(use_nullable_types: True)`).

 

Issue Links

• links to: GitHub Pull Request #11434