org.apache.spark.ml.recommendation

Class ALS.InBlock<ID>

Object

org.apache.spark.ml.recommendation.ALS.InBlock<ID>

All Implemented Interfaces:

java.io.Serializable, scala.Equals, scala.Product

Enclosing class:

ALS

public static class ALS.InBlock<ID>
extends Object
implements scala.Product, scala.Serializable

In-link block for computing src (user/item) factors. This includes the original src IDs of the elements within this block as well as encoded dst (item/user) indices and corresponding ratings. The dst indices are in the form of (blockId, localIndex), which are not the original dst IDs. To compute src factors, we expect receiving dst factors that match the dst indices. For example, if we have an in-link record

{srcId: 0, dstBlockId: 2, dstLocalIndex: 3, rating: 5.0},

and assume that the dst factors are stored as dstFactors: Map[Int, Array[Array[Float}], which is a blockId to dst factors map, the corresponding dst factor of the record is dstFactor(2)(3).

We use a CSC-like (compressed sparse column) format to store the in-link information. So we can compute src factors one after another using only one normal equation instance.

See Also:

ALS.LocalIndexEncoder, Serialized Form

Constructor Summary

Constructors

Constructor and Description
ALS.InBlock(Object srcIds, int[] dstPtrs, int[] dstEncodedIndices, float[] ratings, scala.reflect.ClassTag<ID> evidence$2)

Method Summary

Methods

Modifier and Type	Method and Description
int[]	dstEncodedIndices()
int[]	dstPtrs()
float[]	ratings()
int	size() Size of the block.
Object	srcIds()

Methods inherited from class Object

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

Methods inherited from interface scala.Product

productArity, productElement, productIterator, productPrefix

Methods inherited from interface scala.Equals

canEqual, equals

Constructor Detail

ALS.InBlock

public ALS.InBlock(Object srcIds,
           int[] dstPtrs,
           int[] dstEncodedIndices,
           float[] ratings,
           scala.reflect.ClassTag<ID> evidence$2)

Method Detail

srcIds

public Object srcIds()

dstPtrs

public int[] dstPtrs()

dstEncodedIndices

public int[] dstEncodedIndices()

ratings

public float[] ratings()

size

public int size()

Size of the block.