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From: Alberto Cordioli <cordioli.alberto@gmail.com>
Date: Fri, 5 Oct 2012 12:17:44 +0200
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Subject: Problem in Matrix creation
To: user@hadoop.apache.org
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Hi all,

I am trying to create a matrix NxN with a MapReduce routine.
To do so I need to iterate on a list of values and compare all the
items of the list with each other.
The problem is that in the reduce method only an Iterable<Writable> is
given and with such object you cannot compute all the possible pairs
because I need 2 indexes.
Moreover the Iterable is not clonable.

How can I solve this problem? Is there any standard technique to use?


Thanks,
Alberto


-- 
Alberto Cordioli