org.lenskit.mf.svd

Class DotProductKernel

java.lang.Object

org.lenskit.mf.svd.DotProductKernel

All Implemented Interfaces:

Serializable, BiasedMFKernel

@Shareable
 @Immutable
public class DotProductKernel
extends Object
implements BiasedMFKernel, Serializable

Kernel function that uses the dot product of the user and item vectors.

Since:

2.1

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
DotProductKernel()

Method Summary

Modifier and Type	Method and Description
double	apply(double bias, org.apache.commons.math3.linear.RealVector user, org.apache.commons.math3.linear.RealVector item) Apply the kernel function.
boolean	equals(Object o)
int	hashCode()
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

DotProductKernel

public DotProductKernel()

Method Detail

apply

public double apply(double bias,
                    @Nonnull
                    org.apache.commons.math3.linear.RealVector user,
                    @Nonnull
                    org.apache.commons.math3.linear.RealVector item)

Description copied from interface: BiasedMFKernel

Apply the kernel function.

Specified by:

apply in interface BiasedMFKernel

Parameters:

bias - The combined user-item bias term (the baseline score, usually).

user - The user-factor vector.

item - The item-factor vector.

Returns:

The kernel function value (combined score).

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object