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Olga Natkovich commented on PIG-1150: ------------------------------------- We would like to cut release branch next Monday. This mean that the code needs to be committed by the end of the week. Is this likely to happen? If not, I would like to unlink this from 0.7.0 release and leave for inclusion in one of the future releases when this patch is ready. > VAR() Variance UDF > ------------------ > > Key: PIG-1150 > URL: https://issues.apache.org/jira/browse/PIG-1150 > Project: Pig > Issue Type: New Feature > Affects Versions: 0.5.0 > Environment: UDF, written in Pig 0.5 contrib/ > Reporter: Russell Jurney > Fix For: 0.7.0 > > Attachments: var.patch > > > I've implemented a UDF in Pig 0.5 that implements Algebraic and calculates > variance in a distributed manner, based on the AVG() builtin. It works by > calculating the count, sum and sum of squares, as described here: > http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Parallel_algorithm > Is this a worthwhile contribution? Taking the square root of this value > using the contrib SQRT() function gives Standard Deviation, which is missing > from Pig. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.