You are viewing a plain text version of this content. The canonical link for it is here.

Posted to dev@hive.apache.org by "Mayank Lahiri (JIRA)" <ji...@apache.org> on 2010/05/26 23:53:36 UTC

[jira] Updated: (HIVE-1372) New algorithm for variance() UDAF

     [ https://issues.apache.org/jira/browse/HIVE-1372?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Mayank Lahiri updated HIVE-1372:
--------------------------------

    Attachment: HIVE-VARIANCE.patch

Patchfile for new variance() UDAF

> New algorithm for variance() UDAF
> ---------------------------------
>
>                 Key: HIVE-1372
>                 URL: https://issues.apache.org/jira/browse/HIVE-1372
>             Project: Hadoop Hive
>          Issue Type: Improvement
>          Components: Query Processor
>    Affects Versions: 0.6.0
>            Reporter: Mayank Lahiri
>            Priority: Minor
>             Fix For: 0.6.0
>
>         Attachments: HIVE-1372.patch
>
>
> A new algorithm for the UDAF that computes variance. This is pretty much a drop-in replacement for the current UDAF, and has two benefits: provably numerically stable (reference included in comments), and reduces arithmetic operations by about half.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.