org.apache.spark.ml.recommendation

Class ALS.CholeskySolver

Object

org.apache.spark.ml.recommendation.ALS.CholeskySolver

All Implemented Interfaces:

java.io.Serializable, ALS.LeastSquaresNESolver

Enclosing class:

ALS

public static class ALS.CholeskySolver
extends Object
implements ALS.LeastSquaresNESolver

Cholesky solver for least square problems.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ALS.CholeskySolver()

Method Summary

Methods

Modifier and Type	Method and Description
float[]	solve(ALS.NormalEquation ne, double lambda) Solves a least squares problem with L2 regularization:

Methods inherited from class Object

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

Constructor Detail

ALS.CholeskySolver

public ALS.CholeskySolver()

Method Detail

solve

public float[] solve(ALS.NormalEquation ne,
            double lambda)

Solves a least squares problem with L2 regularization:

min norm(A x - b)^2^ + lambda * norm(x)^2^

Specified by:

solve in interface ALS.LeastSquaresNESolver

Parameters:

ne - a ALS.NormalEquation instance that contains AtA, Atb, and n (number of instances)

lambda - regularization constant

Returns:

the solution x