[
https://issues.apache.org/jira/browse/HBASE-5142?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13182308#comment-13182308
]
Zhihong Yu commented on HBASE-5142:
-----------------------------------
AggregationClient.std() already provides this capability.
> Compute standard deviation using AggregateProtocol
> --------------------------------------------------
>
> Key: HBASE-5142
> URL: https://issues.apache.org/jira/browse/HBASE-5142
> Project: HBase
> Issue Type: Sub-task
> Reporter: Zhihong Yu
>
> Looking at http://en.wikipedia.org/wiki/Standard_deviation, I think two
> passes are involved in computing std:
> 1. compute average, u
> 2. tuple of (sum of (xi-u)*(xi-u), number of rows) is returned from each
> region
> 3. client computes std based on results from step 2
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
