Package org.jscience.mathematics.vector

Class SparseVector<F extends Field<F>>

java.lang.Object
org.jscience.mathematics.vector.Vector<F>
org.jscience.mathematics.vector.SparseVector<F>
All Implemented Interfaces:
javolution.lang.Immutable, javolution.lang.Realtime, javolution.lang.ValueType, GroupAdditive<Vector<F>>, Structure<Vector<F>>, VectorSpace<Vector<F>,F>
public final class SparseVector<F extends Field<F>> extends Vector<F>

This class represents a sparse vector.

Sparse vectors can be created using an index-to-element mapping or by adding single elements sparse vectors together.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected static final javolution.xml.XMLFormat<SparseVector>
    XML
    Holds the default XML representation for sparse vectors.

  • Method Summary

    Modifier and Type
    Method
    Description
    SparseVector<F>
    copy()
    Returns a copy of this vector allocated by the calling thread (possibly on the stack).
    F
    get(int i)
    Returns a single element from this vector.
    int
    getDimension()
    Returns the number of elements held by this vector.
    F
    getZero()
    Returns the value of the non-set elements for this sparse vector.
    SparseVector<F>
    opposite()
    Returns the negation of this vector.
    SparseVector<F>
    plus(Vector<F> that)
    Returns the sum of this vector with the one specified.
    SparseVector<F>
    times(F k)
    Returns the product of this vector with the specified coefficient.
    F
    times(Vector<F> that)
    Returns the dot product of this vector with the one specified.
    static <F extends Field<F>>
    SparseVector<F>
    valueOf(int dimension, F zero, int i, F element)
    Returns a sparse vector having a single element at the specified index.
    static <F extends Field<F>>
    SparseVector<F>
    valueOf(int dimension, F zero, Map<javolution.util.Index,F> elements)
    Returns a sparse vector from the specified index to element mapping.
    static <F extends Field<F>>
    SparseVector<F>
    valueOf(Vector<F> that, F zero)
    Returns a sparse vector equivalent to the specified vector but with the zero elements removed removed using a default object equality comparator.
    static <F extends Field<F>>
    SparseVector<F>
    valueOf(Vector<F> that, F zero, javolution.util.FastComparator<? super F> comparator)
    Returns a sparse vector equivalent to the specified vector but with the zero elements removed using the specified object equality comparator.

    Methods inherited from class org.jscience.mathematics.vector.Vector

    cross, equals, equals, hashCode, minus, toString, toText

    Methods inherited from class java.lang.Object

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

  • Field Details

    • XML

      protected static final javolution.xml.XMLFormat<SparseVector> XML
      Holds the default XML representation for sparse vectors. For example:[code] [/code]

  • Method Details

    • valueOf

      public static <F extends Field<F>> SparseVector<F> valueOf(int dimension, F zero, int i, F element)
      Returns a sparse vector having a single element at the specified index.
      Parameters:
      dimension - this vector dimension.
      zero - the element representing zero.
      i - the index value of this vector single element.
      element - the element at the specified index.
      Returns:
      the corresponding vector.

    • valueOf

      public static <F extends Field<F>> SparseVector<F> valueOf(int dimension, F zero, Map<javolution.util.Index,F> elements)
      Returns a sparse vector from the specified index to element mapping.
      Parameters:
      dimension - this vector dimension.
      zero - the element representing zero.
      elements - the index to element mapping.
      Returns:
      the corresponding vector.

    • valueOf

      public static <F extends Field<F>> SparseVector<F> valueOf(Vector<F> that, F zero)
      Returns a sparse vector equivalent to the specified vector but with the zero elements removed removed using a default object equality comparator.
      Parameters:
      that - the vector to convert.
      zero - the zero element for the sparse vector to return.
      Returns:
      SparseVector.valueOf(that, zero, FastComparator.DEFAULT)

    • valueOf

      public static <F extends Field<F>> SparseVector<F> valueOf(Vector<F> that, F zero, javolution.util.FastComparator<? super F> comparator)
      Returns a sparse vector equivalent to the specified vector but with the zero elements removed using the specified object equality comparator. This method can be used to clean up sparse vectors (to remove elements close to zero).
      Parameters:
      that - the vector to convert.
      zero - the zero element for the sparse vector to return.
      comparator - the comparator used to determinate zero equality.
      Returns:
      a sparse vector with zero elements removed.

    • getZero

      public F getZero()
      Returns the value of the non-set elements for this sparse vector.
      Returns:
      the element corresponding to zero.

    • getDimension

      public int getDimension()
      Description copied from class: Vector
      Returns the number of elements held by this vector.
      Specified by:
      getDimension in class Vector<F extends Field<F>>
      Returns:
      this vector dimension.

    • get

      public F get(int i)
      Description copied from class: Vector
      Returns a single element from this vector.
      Specified by:
      get in class Vector<F extends Field<F>>
      Parameters:
      i - the element index (range [0..n[).
      Returns:
      the element at i.

    • opposite

      public SparseVector<F> opposite()
      Description copied from class: Vector
      Returns the negation of this vector.
      Specified by:
      opposite in interface GroupAdditive<F extends Field<F>>
      Specified by:
      opposite in class Vector<F extends Field<F>>
      Returns:
      -this.

    • plus

      public SparseVector<F> plus(Vector<F> that)
      Description copied from class: Vector
      Returns the sum of this vector with the one specified.
      Specified by:
      plus in interface GroupAdditive<F extends Field<F>>
      Specified by:
      plus in class Vector<F extends Field<F>>
      Parameters:
      that - the vector to be added.
      Returns:
      this + that.

    • times

      public SparseVector<F> times(F k)
      Description copied from class: Vector
      Returns the product of this vector with the specified coefficient.
      Specified by:
      times in interface VectorSpace<Vector<F extends Field<F>>,F extends Field<F>>
      Specified by:
      times in class Vector<F extends Field<F>>
      Parameters:
      k - the coefficient multiplier.
      Returns:
      this · k

    • times

      public F times(Vector<F> that)
      Description copied from class: Vector
      Returns the dot product of this vector with the one specified.
      Specified by:
      times in class Vector<F extends Field<F>>
      Parameters:
      that - the vector multiplier.
      Returns:
      this · that
      See Also:

    • copy

      public SparseVector<F> copy()
      Description copied from class: Vector
      Returns a copy of this vector allocated by the calling thread (possibly on the stack).
      Specified by:
      copy in interface javolution.lang.ValueType
      Specified by:
      copy in class Vector<F extends Field<F>>
      Returns:
      an identical and independant copy of this matrix.