uk.ac.gla.dcs.renaissance.kqpr
Class KernelVectorList<T extends KernelVector>

java.lang.Object
  java.util.AbstractCollection<E>
      java.util.AbstractList<T>
          uk.ac.gla.dcs.renaissance.kqpr.KernelVectorList<T>

All Implemented Interfaces:

Iterable<T>, Collection<T>, List<T>

Direct Known Subclasses:

SparseVectors

public abstract class KernelVectorList<T extends KernelVector>
extends AbstractList<T>

This class holds a list of vectors whose exact representation might not be known. All sub-classes must implement basic list operations (add, remove).

Author:

B. Piwowarski

Field Summary

Fields inherited from class java.util.AbstractList

modCount

Constructor Summary

KernelVectorList()

Method Summary

boolean	canLinearlyCombine() Returns true if the vectors can be linearly combined
abstract double	computeInnerProduct(int i, T vector) Computes the inner product between a given vector and the ith vector of the list
protected bpiwowar.maths.matrix.DenseDoubleMatrix2D	computeInnerProducts(KernelVectorList<T> other)
double[]	computeInnerProducts(T vector) Compute the inner products with each of the vectors.
T	linearCombination(double[] lambdas) Computes a linear combination.

Methods inherited from class java.util.AbstractList

add, add, addAll, clear, equals, get, hashCode, indexOf, iterator, lastIndexOf, listIterator, listIterator, remove, removeRange, set, subList

Methods inherited from class java.util.AbstractCollection

addAll, contains, containsAll, isEmpty, remove, removeAll, retainAll, size, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.List

addAll, contains, containsAll, isEmpty, remove, removeAll, retainAll, size, toArray, toArray

Constructor Detail

KernelVectorList

public KernelVectorList()

Method Detail

computeInnerProduct

public abstract double computeInnerProduct(int i,
                                           T vector)

Computes the inner product between a given vector and the i^th vector of the list

Parameters:

i - The index of the vector in the list

vector - The vector provided

Returns:

The inner product between both vectors

computeInnerProducts

protected bpiwowar.maths.matrix.DenseDoubleMatrix2D computeInnerProducts(KernelVectorList<T> other)

computeInnerProducts

public double[] computeInnerProducts(T vector)

Compute the inner products with each of the vectors. This method might be re-implemented for efficiency reason, and by default calls iteratively #computeInnerProduct(int, Object).

Parameters:

vector - The vector with which the inner product is computed each time

Returns:

A series of inner products, one for each of the base vectors

canLinearlyCombine

public boolean canLinearlyCombine()

Returns true if the vectors can be linearly combined

linearCombination

public T linearCombination(double[] lambdas)
                                         throws UnsupportedOperationException

Computes a linear combination.

Returns:

a new BaseVectorList object

Throws:

UnsupportedOperationException - If the object does not support linear combinations. This is implied if canLinearlyCombine() returns false