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From Susheel Kumar Gadalay <skgada...@gmail.com>
Subject Re: Split files into 80% and 20% for building model and prediction
Date Fri, 12 Dec 2014 09:58:39 GMT
Simple solution..

Copy the HDFS file to local and use OS commands to count no of lines

cat file1 | wc -l

and cut it based on line number.


On 12/12/14, unmesha sreeveni <unmeshabiju@gmail.com> wrote:
> I am trying to divide my HDFS file into 2 parts/files
> 80% and 20% for classification algorithm(80% for modelling and 20% for
> prediction)
> Please provide suggestion for the same.
> To take 80% and 20% to 2 seperate files we need to know the exact number of
> record in the data set
> And it is only known if we go through the data set once.
> so we need to write 1 MapReduce Job for just counting the number of records
> and
> 2 nd Mapreduce Job for separating 80% and 20% into 2 files using Multiple
> Inputs.
>
>
> Am I in the right track or there is any alternative for the same.
> But again a small confusion how to check if the reducer get filled with 80%
> data.
>
>
> --
> *Thanks & Regards *
>
>
> *Unmesha Sreeveni U.B*
> *Hadoop, Bigdata Developer*
> *Centre for Cyber Security | Amrita Vishwa Vidyapeetham*
> http://www.unmeshasreeveni.blogspot.in/
>

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