org.apache.mahout.cf.taste.hadoop.item

Class SimilarityMatrixRowWrapperMapper

java.lang.Object

org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.IntWritable,VectorWritable,VarIntWritable,VectorOrPrefWritable>

org.apache.mahout.cf.taste.hadoop.item.SimilarityMatrixRowWrapperMapper

public final class SimilarityMatrixRowWrapperMapper
extends org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.IntWritable,VectorWritable,VarIntWritable,VectorOrPrefWritable>

maps a row of the similarity matrix to a VectorOrPrefWritable actually a column from that matrix has to be used but as the similarity matrix is symmetric, we can use a row instead of having to transpose it

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Mapper

org.apache.hadoop.mapreduce.Mapper.Context

Constructor Summary

Constructors

Constructor and Description
SimilarityMatrixRowWrapperMapper()

Method Summary

Modifier and Type	Method and Description
protected void	map(org.apache.hadoop.io.IntWritable key, VectorWritable value, org.apache.hadoop.mapreduce.Mapper.Context context)

Methods inherited from class org.apache.hadoop.mapreduce.Mapper

cleanup, run, setup

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SimilarityMatrixRowWrapperMapper

public SimilarityMatrixRowWrapperMapper()

Method Detail

map

protected void map(org.apache.hadoop.io.IntWritable key,
                   VectorWritable value,
                   org.apache.hadoop.mapreduce.Mapper.Context context)
            throws IOException,
                   InterruptedException

Overrides:

map in class org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.IntWritable,VectorWritable,VarIntWritable,VectorOrPrefWritable>

Throws:

IOException

InterruptedException