## org.apache.commons.math.linear
Interface FieldVector<T extends FieldElement<T>>

Type Parameters:
  `T` - the type of the field elements

All Known Implementing Classes:
  ArrayFieldVector, SparseFieldVector

    public interface FieldVector<T extends FieldElement<T>>

Interface defining a field-valued vector with basic algebraic operations.

vector element indexing is 0-based -- e.g., `getEntry(0)` returns the first element of the vector.

The various `mapXxx` and `mapXxxToSelf` methods operate on vectors element-wise, i.e. they perform the same operation (adding a scalar, applying a function ...) on each element in turn. The `mapXxx` versions create a new vector to hold the result and do not change the instance. The `mapXxxToSelf` versions use the instance itself to store the results, so the instance is changed by these methods. In both cases, the result vector is returned by the methods, this allows to use the fluent API style, like this:

       RealVector result = v.mapAddToSelf(3.0).mapTanToSelf().mapSquareToSelf();

Since:
  2.0
Version:
  $Revision: 811786 $ $Date: 2009-09-06 05:36:08 -0400 (Sun, 06 Sep 2009) $

Method Summary
`FieldVector<T>` `add(FieldVector<T> v)` Compute the sum of this and v.
`FieldVector<T>` `add(T[] v)` Compute the sum of this and v.
`FieldVector<T>` `append(FieldVector<T> v)` Construct a vector by appending a vector to this vector.
`FieldVector<T>` `append(T d)` Construct a vector by appending a T to this vector.
`FieldVector<T>` `append(T[] a)` Construct a vector by appending a T array to this vector.
`FieldVector<T>` `copy()` Returns a (deep) copy of this.
`T` `dotProduct(FieldVector<T> v)` Compute the dot product.
`T` `dotProduct(T[] v)` Compute the dot product.
`FieldVector<T>` `ebeDivide(FieldVector<T> v)` Element-by-element division.
`FieldVector<T>` `ebeDivide(T[] v)` Element-by-element division.
`FieldVector<T>` `ebeMultiply(FieldVector<T> v)` Element-by-element multiplication.
`FieldVector<T>` `ebeMultiply(T[] v)` Element-by-element multiplication.
`T[]` `getData()` Returns vector entries as a T array.
`int` `getDimension()` Returns the size of the vector.
`T` `getEntry(int index)` Returns the entry in the specified index.
`Field<T>` `getField()` Get the type of field elements of the vector.
`FieldVector<T>` `getSubVector(int index, int n)` Get a subvector from consecutive elements.
`FieldVector<T>` `mapAdd(T d)` Map an addition operation to each entry.
`FieldVector<T>` `mapAddToSelf(T d)` Map an addition operation to each entry.
`FieldVector<T>` `mapDivide(T d)` Map a division operation to each entry.
`FieldVector<T>` `mapDivideToSelf(T d)` Map a division operation to each entry.
`FieldVector<T>` `mapInv()` Map the 1/x function to each entry.
`FieldVector<T>` `mapInvToSelf()` Map the 1/x function to each entry.
`FieldVector<T>` `mapMultiply(T d)` Map a multiplication operation to each entry.
`FieldVector<T>` `mapMultiplyToSelf(T d)` Map a multiplication operation to each entry.
`FieldVector<T>` `mapSubtract(T d)` Map a subtraction operation to each entry.
`FieldVector<T>` `mapSubtractToSelf(T d)` Map a subtraction operation to each entry.
`FieldMatrix<T>` `outerProduct(FieldVector<T> v)` Compute the outer product.
`FieldMatrix<T>` `outerProduct(T[] v)` Compute the outer product.
`FieldVector<T>` `projection(FieldVector<T> v)` Find the orthogonal projection of this vector onto another vector.
`FieldVector<T>` `projection(T[] v)` Find the orthogonal projection of this vector onto another vector.
`void` `set(T value)` Set all elements to a single value.
`void` `setEntry(int index, T value)` Set a single element.
`void` `setSubVector(int index, FieldVector<T> v)` Set a set of consecutive elements.
`void` `setSubVector(int index, T[] v)` Set a set of consecutive elements.
`FieldVector<T>` `subtract(FieldVector<T> v)` Compute this minus v.
`FieldVector<T>` `subtract(T[] v)` Compute this minus v.
`T[]` `toArray()` Convert the vector to a T array.

Method Detail

### getField

    Field<T> getField()

  Get the type of field elements of the vector.

  Returns:
    type of field elements of the vector

### copy

    FieldVector<T> copy()

  Returns a (deep) copy of this.

  Returns:
    vector copy

### add

    FieldVector<T> add(FieldVector<T> v)
                                               throws java.lang.IllegalArgumentException

  Compute the sum of this and v.

  Parameters:
    `v` - vector to be added
  Returns:
    this + v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### add

    FieldVector<T> add(T[] v)
                                               throws java.lang.IllegalArgumentException

  Compute the sum of this and v.

  Parameters:
    `v` - vector to be added
  Returns:
    this + v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### subtract

    FieldVector<T> subtract(FieldVector<T> v)
                                                    throws java.lang.IllegalArgumentException

  Compute this minus v.

  Parameters:
    `v` - vector to be subtracted
  Returns:
    this + v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### subtract

    FieldVector<T> subtract(T[] v)
                                                    throws java.lang.IllegalArgumentException

  Compute this minus v.

  Parameters:
    `v` - vector to be subtracted
  Returns:
    this + v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### mapAdd

    FieldVector<T> mapAdd(T d)

  Map an addition operation to each entry.

  Parameters:
    `d` - value to be added to each entry
  Returns:
    this + d

### mapAddToSelf

    FieldVector<T> mapAddToSelf(T d)

  Map an addition operation to each entry.

  The instance is changed by this method.

  Parameters:
    `d` - value to be added to each entry
  Returns:
    for convenience, return this

### mapSubtract

    FieldVector<T> mapSubtract(T d)

  Map a subtraction operation to each entry.

  Parameters:
    `d` - value to be subtracted to each entry
  Returns:
    this - d

### mapSubtractToSelf

    FieldVector<T> mapSubtractToSelf(T d)

  Map a subtraction operation to each entry.

  The instance is changed by this method.

  Parameters:
    `d` - value to be subtracted to each entry
  Returns:
    for convenience, return this

### mapMultiply

    FieldVector<T> mapMultiply(T d)

  Map a multiplication operation to each entry.

  Parameters:
    `d` - value to multiply all entries by
  Returns:
    this * d

### mapMultiplyToSelf

    FieldVector<T> mapMultiplyToSelf(T d)

  Map a multiplication operation to each entry.

  The instance is changed by this method.

  Parameters:
    `d` - value to multiply all entries by
  Returns:
    for convenience, return this

### mapDivide

    FieldVector<T> mapDivide(T d)

  Map a division operation to each entry.

  Parameters:
    `d` - value to divide all entries by
  Returns:
    this / d

### mapDivideToSelf

    FieldVector<T> mapDivideToSelf(T d)

  Map a division operation to each entry.

  The instance is changed by this method.

  Parameters:
    `d` - value to divide all entries by
  Returns:
    for convenience, return this

### mapInv

    FieldVector<T> mapInv()

  Map the 1/x function to each entry.

  Returns:
    a vector containing the result of applying the function to each entry

### mapInvToSelf

    FieldVector<T> mapInvToSelf()

  Map the 1/x function to each entry.

  The instance is changed by this method.

  Returns:
    for convenience, return this

### ebeMultiply

    FieldVector<T> ebeMultiply(FieldVector<T> v)
                                                       throws java.lang.IllegalArgumentException

  Element-by-element multiplication.

  Parameters:
    `v` - vector by which instance elements must be multiplied
  Returns:
    a vector containing this[i] * v[i] for all i
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### ebeMultiply

    FieldVector<T> ebeMultiply(T[] v)
                                                       throws java.lang.IllegalArgumentException

  Element-by-element multiplication.

  Parameters:
    `v` - vector by which instance elements must be multiplied
  Returns:
    a vector containing this[i] * v[i] for all i
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### ebeDivide

    FieldVector<T> ebeDivide(FieldVector<T> v)
                                                     throws java.lang.IllegalArgumentException

  Element-by-element division.

  Parameters:
    `v` - vector by which instance elements must be divided
  Returns:
    a vector containing this[i] / v[i] for all i
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### ebeDivide

    FieldVector<T> ebeDivide(T[] v)
                                                     throws java.lang.IllegalArgumentException

  Element-by-element division.

  Parameters:
    `v` - vector by which instance elements must be divided
  Returns:
    a vector containing this[i] / v[i] for all i
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### getData

    T[] getData()

  Returns vector entries as a T array.

  Returns:
    T array of entries

### dotProduct

    T dotProduct(FieldVector<T> v)
                                         throws java.lang.IllegalArgumentException

  Compute the dot product.

  Parameters:
    `v` - vector with which dot product should be computed
  Returns:
    the scalar dot product between instance and v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### dotProduct

    T dotProduct(T[] v)
                                         throws java.lang.IllegalArgumentException

  Compute the dot product.

  Parameters:
    `v` - vector with which dot product should be computed
  Returns:
    the scalar dot product between instance and v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### projection

    FieldVector<T> projection(FieldVector<T> v)
                                                      throws java.lang.IllegalArgumentException

  Find the orthogonal projection of this vector onto another vector.

  Parameters:
    `v` - vector onto which instance must be projected
  Returns:
    projection of the instance onto v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### projection

    FieldVector<T> projection(T[] v)
                                                      throws java.lang.IllegalArgumentException

  Find the orthogonal projection of this vector onto another vector.

  Parameters:
    `v` - vector onto which instance must be projected
  Returns:
    projection of the instance onto v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### outerProduct

    FieldMatrix<T> outerProduct(FieldVector<T> v)
                                                        throws java.lang.IllegalArgumentException

  Compute the outer product.

  Parameters:
    `v` - vector with which outer product should be computed
  Returns:
    the square matrix outer product between instance and v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### outerProduct

    FieldMatrix<T> outerProduct(T[] v)
                                                        throws java.lang.IllegalArgumentException

  Compute the outer product.

  Parameters:
    `v` - vector with which outer product should be computed
  Returns:
    the square matrix outer product between instance and v
  Throws:
    `java.lang.IllegalArgumentException` - if v is not the same size as this

### getEntry

    T getEntry(int index)
                                       throws MatrixIndexException

  Returns the entry in the specified index.

  The index start at 0 and must be lesser than the size, otherwise a `MatrixIndexException` is thrown.

  Parameters:
    `index` - index location of entry to be fetched
  Returns:
    vector entry at index
  Throws:
    `MatrixIndexException` - if the index is not valid
  See Also:
    `setEntry(int, FieldElement)`

### setEntry

    void setEntry(int index,
                  T value)
                  throws MatrixIndexException

  Set a single element.

  Parameters:
    `index` - element index.
    `value` - new value for the element.
  Throws:
    `MatrixIndexException` - if the index is inconsistent with vector size
  See Also:
    `getEntry(int)`

### getDimension

    int getDimension()

  Returns the size of the vector.

  Returns:
    size

### append

    FieldVector<T> append(FieldVector<T> v)

  Construct a vector by appending a vector to this vector.

  Parameters:
    `v` - vector to append to this one.
  Returns:
    a new vector

### append

    FieldVector<T> append(T d)

  Construct a vector by appending a T to this vector.

  Parameters:
    `d` - T to append.
  Returns:
    a new vector

### append

    FieldVector<T> append(T[] a)

  Construct a vector by appending a T array to this vector.

  Parameters:
    `a` - T array to append.
  Returns:
    a new vector

### getSubVector

    FieldVector<T> getSubVector(int index,
                                int n)
                                                        throws MatrixIndexException

  Get a subvector from consecutive elements.

  Parameters:
    `index` - index of first element.
    `n` - number of elements to be retrieved.
  Returns:
    a vector containing n elements.
  Throws:
    `MatrixIndexException` - if the index is inconsistent with vector size

### setSubVector

    void setSubVector(int index,
                      FieldVector<T> v)
                      throws MatrixIndexException

  Set a set of consecutive elements.

  Parameters:
    `index` - index of first element to be set.
    `v` - vector containing the values to set.
  Throws:
    `MatrixIndexException` - if the index is inconsistent with vector size
  See Also:
    `setSubVector(int, FieldElement[])`

### setSubVector

    void setSubVector(int index,
                      T[] v)
                      throws MatrixIndexException

  Set a set of consecutive elements.

  Parameters:
    `index` - index of first element to be set.
    `v` - vector containing the values to set.
  Throws:
    `MatrixIndexException` - if the index is inconsistent with vector size
  See Also:
    `setSubVector(int, FieldVector)`

### set

    void set(T value)

  Set all elements to a single value.

  Parameters:
    `value` - single value to set for all elements

### toArray

    T[] toArray()

  Convert the vector to a T array.

  The array is independent from vector data, it's elements are copied.

  Returns:
    array containing a copy of vector elements

Copyright (c) 2003-2010 Apache Software Foundation