org.apache.mahout.math.hadoop.stochasticsvd

Class SparseRowBlockWritable

java.lang.Object

org.apache.mahout.math.hadoop.stochasticsvd.SparseRowBlockWritable

All Implemented Interfaces:

org.apache.hadoop.io.Writable

public class SparseRowBlockWritable
extends Object
implements org.apache.hadoop.io.Writable

block that supports accumulating rows and their sums , suitable for combiner and reducers of multiplication jobs.

Constructor Summary

Constructors

Constructor and Description
SparseRowBlockWritable()
SparseRowBlockWritable(int initialCapacity)

Method Summary

Modifier and Type	Method and Description
void	clear()
int	getNumRows()
int[]	getRowIndices()
Vector[]	getRows()
void	plusBlock(SparseRowBlockWritable bOther) pluses one block into another.
void	plusRow(int index, Vector row)
void	readFields(DataInput in)
void	write(DataOutput out)

Methods inherited from class java.lang.Object

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

Constructor Detail

SparseRowBlockWritable

public SparseRowBlockWritable()

SparseRowBlockWritable

public SparseRowBlockWritable(int initialCapacity)

Method Detail

getRowIndices

public int[] getRowIndices()

getRows

public Vector[] getRows()

readFields

public void readFields(DataInput in)
                throws IOException

Specified by:

readFields in interface org.apache.hadoop.io.Writable

Throws:

IOException

write

public void write(DataOutput out)
           throws IOException

Specified by:

write in interface org.apache.hadoop.io.Writable

Throws:

IOException

plusRow

public void plusRow(int index,
                    Vector row)

plusBlock

public void plusBlock(SparseRowBlockWritable bOther)

pluses one block into another. Use it for accumulation of partial products in combiners and reducers.

Parameters:

bOther - block to add

getNumRows

public int getNumRows()

clear

public void clear()