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Shashikant Kore commented on MAHOUT-208: ---------------------------------------- Apologies. I *assumed* underlying library already does some caching for hash value. String does cache, but it is immutable, so it is "obvious." Caching hashcode for mutable object will face the same problems as us. > Vector.getLengthSquared() is dangerously optimized > -------------------------------------------------- > > Key: MAHOUT-208 > URL: https://issues.apache.org/jira/browse/MAHOUT-208 > Project: Mahout > Issue Type: Bug > Components: Matrix > Affects Versions: 0.1 > Environment: all > Reporter: Jake Mannix > Assignee: Sean Owen > Fix For: 0.3 > > > SparseVector and DenseVector both cache the value of lengthSquared, so that > subsequent calls to it get the cached value. Great, except the cache is > never cleared - calls to set/setQuick or assign or anything, all leave the > cached value unchanged. > Mutating method calls should set lengthNorm to -1 so that the cache is > cleared. > This could be a really nasty bug if hit. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.