[
https://issues.apache.org/jira/browse/ARROW-56?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17657157#comment-17657157
]
Rok Mihevc commented on ARROW-56:
---------------------------------
This issue has been migrated to [issue
#15467|https://github.com/apache/arrow/issues/15467] on GitHub. Please see the
[migration documentation|https://github.com/apache/arrow/issues/14542] for
further details.
> Format: Specify LSB bit ordering in bit arrays
> ----------------------------------------------
>
> Key: ARROW-56
> URL: https://issues.apache.org/jira/browse/ARROW-56
> Project: Apache Arrow
> Issue Type: New Feature
> Components: Format
> Reporter: Wes McKinney
> Assignee: Wes McKinney
> Priority: Major
> Fix For: 0.1.0
>
>
> In https://github.com/apache/arrow/blob/master/format/Layout.md, we describe
> bitmaps for nulls (presumably same encoding for boolean data) and provide the
> C code for accessing a bit:
> {{bitmask[j / 8] & (1 << (j % 8))}}
> Implicitly this is LSB bit-endianness
> (https://en.wikipedia.org/wiki/Bit_numbering) -- see the discussion of
> bitpacking in the Parquet format:
> https://github.com/apache/parquet-format/blob/master/Encodings.md#run-length-encoding--bit-packing-hybrid-rle--3
> If this is what we want, we should make this aspect of the format explicit.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
