org.apache.mahout.math

Class VectorBinaryAssign.AssignNonzerosIterateThisLookupThat

java.lang.Object

org.apache.mahout.math.VectorBinaryAssign

org.apache.mahout.math.VectorBinaryAssign.AssignNonzerosIterateThisLookupThat

Enclosing class:

VectorBinaryAssign

public static class VectorBinaryAssign.AssignNonzerosIterateThisLookupThat
extends VectorBinaryAssign

If f(0, y) = 0, the zeros in x don't matter and we can simply iterate through the nonzeros of x. To get the corresponding element of y, we perform a lookup. There are no *Merge or *Inplace versions because in this case x cannot become more dense because of f, meaning all changes will occur at indices whose values are already nonzero.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.mahout.math.VectorBinaryAssign

VectorBinaryAssign.AssignAllIterateSequentialInplaceUpdates, VectorBinaryAssign.AssignAllIterateSequentialMergeUpdates, VectorBinaryAssign.AssignAllIterateThatLookupThisInplaceUpdates, VectorBinaryAssign.AssignAllIterateThatLookupThisMergeUpdates, VectorBinaryAssign.AssignAllIterateThisLookupThatInplaceUpdates, VectorBinaryAssign.AssignAllIterateThisLookupThatMergeUpdates, VectorBinaryAssign.AssignAllLoopInplaceUpdates, VectorBinaryAssign.AssignAllLoopMergeUpdates, VectorBinaryAssign.AssignIterateIntersection, VectorBinaryAssign.AssignIterateUnionRandomInplaceUpdates, VectorBinaryAssign.AssignIterateUnionRandomMergeUpdates, VectorBinaryAssign.AssignIterateUnionSequentialInplaceUpdates, VectorBinaryAssign.AssignIterateUnionSequentialMergeUpdates, VectorBinaryAssign.AssignNonzerosIterateThatLookupThisInplaceUpdates, VectorBinaryAssign.AssignNonzerosIterateThatLookupThisMergeUpdates, VectorBinaryAssign.AssignNonzerosIterateThisLookupThat

Field Summary

Fields inherited from class org.apache.mahout.math.VectorBinaryAssign

OPERATIONS

Constructor Summary

Constructors

Constructor and Description
VectorBinaryAssign.AssignNonzerosIterateThisLookupThat()

Method Summary

Methods

Modifier and Type	Method and Description
Vector	assign(Vector x, Vector y, DoubleDoubleFunction f) Main method that applies f to x and y component-wise assigning the results to x.
double	estimateCost(Vector x, Vector y, DoubleDoubleFunction f) Estimates the cost of using this algorithm to compute the assignment.
boolean	isValid(Vector x, Vector y, DoubleDoubleFunction f) Returns true iff we can use this algorithm to apply f to x and y component-wise and assign the result to x.

Methods inherited from class org.apache.mahout.math.VectorBinaryAssign

assignBest, getBestOperation

Methods inherited from class java.lang.Object

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

Constructor Detail

VectorBinaryAssign.AssignNonzerosIterateThisLookupThat

public VectorBinaryAssign.AssignNonzerosIterateThisLookupThat()

Method Detail

isValid

public boolean isValid(Vector x,
              Vector y,
              DoubleDoubleFunction f)

Description copied from class: VectorBinaryAssign

Returns true iff we can use this algorithm to apply f to x and y component-wise and assign the result to x.

Specified by:

isValid in class VectorBinaryAssign

estimateCost

public double estimateCost(Vector x,
                  Vector y,
                  DoubleDoubleFunction f)

Description copied from class: VectorBinaryAssign

Estimates the cost of using this algorithm to compute the assignment. The algorithm is assumed to be valid.

Specified by:

estimateCost in class VectorBinaryAssign

assign

public Vector assign(Vector x,
            Vector y,
            DoubleDoubleFunction f)

Description copied from class: VectorBinaryAssign

Main method that applies f to x and y component-wise assigning the results to x. It returns the modified vector, x.

Specified by:

assign in class VectorBinaryAssign