java.lang.Object
- weka.core.matrix.DoubleVector

All Implemented Interfaces:

java.lang.Cloneable, RevisionHandler
```
public class DoubleVector
extends java.lang.Object
implements java.lang.Cloneable, RevisionHandler
```
A vector specialized on doubles.

Version:

$Revision: 1.4 $

Author:

Yong Wang

Constructor Summary

Constructors
Constructor	Description
`DoubleVector()`	Constructs a null vector.
`DoubleVector(double[] v)`	Constructs a vector directly from a double array
`DoubleVector(int n)`	Constructs an n-vector of zeros.
`DoubleVector(int n, double s)`	Constructs a constant n-vector.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`addElement(double x)`	Adds an element into the vector
`int`	`capacity()`	Gets the capacity of the vector.
`DoubleVector`	`cat(DoubleVector v)`	Combine two vectors together
`java.lang.Object`	`clone()`	Clones the DoubleVector object.
`DoubleVector`	`copy()`	Makes a deep copy of the vector
`DoubleVector`	`cumulate()`	Returns a vector that stores the cumulated values of the original vector
`DoubleVector`	`cumulateInPlace()`	Cumulates the original vector in place
`DoubleVector`	`dividedBy(DoubleVector v)`	Divided by another DoubleVector element by element
`DoubleVector`	`dividedByEquals(DoubleVector v)`	Divided by another DoubleVector element by element in place
`double`	`get(int i)`	Gets a single element.
`double[]`	`getArray()`	Access the internal one-dimensional array.
`double[]`	`getArrayCopy()`	Returns a copy of the DoubleVector usng a double array.
`java.lang.String`	`getRevision()`	Returns the revision string.
`int`	`indexOfMax()`	Returns the index of the maximum.
`double`	`innerProduct(DoubleVector v)`	Returns the inner product of two DoubleVectors
`boolean`	`isEmpty()`	Checks if it is an empty vector
`static void`	`main(java.lang.String[] args)`
`DoubleVector`	`map(java.lang.String className, java.lang.String method)`	Applies a method to the vector
`double`	`max()`	Returns the maximum value of all elements
`DoubleVector`	`minus(double x)`	Subtracts a value
`DoubleVector`	`minus(DoubleVector v)`	Subtracts another DoubleVector element by element
`DoubleVector`	`minusEquals(double x)`	Subtracts a value in place
`DoubleVector`	`minusEquals(DoubleVector v)`	Subtracts another DoubleVector element by element in place
`double`	`norm1()`	Returns the L1-norm of the vector
`double`	`norm2()`	Returns the L2-norm of the vector
`DoubleVector`	`plus(double x)`	Adds a value to all the elements
`DoubleVector`	`plus(DoubleVector v)`	Adds another vector element by element
`DoubleVector`	`plusEquals(double x)`	Adds a value to all the elements in place
`DoubleVector`	`plusEquals(DoubleVector v)`	Adds another vector in place element by element
`static DoubleVector`	`random(int n)`	Returns a random vector of uniform distribution
`DoubleVector`	`rev()`	Returns the reverse vector
`void`	`set(double s)`	Set all elements to a value
`void`	`set(int i, double s)`	Set a single element.
`void`	`set(int i0, int i1, double s)`	Set some elements to a value
`void`	`set(int i0, int i1, double[] v, int j0)`	Set some elements using a 2-D array
`void`	`set(int i0, int i1, DoubleVector v, int j0)`	Set some elements using a DoubleVector.
`void`	`set(DoubleVector v)`	Set the elements using a DoubleVector
`void`	`setCapacity(int n)`	Sets the capacity of the vector
`void`	`setPlus(int i, double s)`	Adds a value to an element
`void`	`setSize(int m)`	Sets the size of the vector
`void`	`setTimes(int i, double s)`	Multiplies a value to an element
`DoubleVector`	`sign()`	Returns the signs of all elements in terms of -1, 0 and +1.
`int`	`size()`	Gets the size of the vector.
`void`	`sort()`	Sorts the array in place
`IntVector`	`sortWithIndex()`	Sorts the array in place with index returned
`void`	`sortWithIndex(int xi, int xj, IntVector index)`	Sorts the array in place with index changed
`DoubleVector`	`sqrt()`	Returns the square-root of all the elements in the vector
`DoubleVector`	`square()`	Returns the squared vector
`DoubleVector`	`subvector(int i0, int i1)`	Returns a subvector.
`DoubleVector`	`subvector(IntVector index)`	Returns a subvector.
`double`	`sum()`	Returns the sum of all elements in the vector.
`double`	`sum2()`	Returns the squared sum of all elements in the vector.
`double`	`sum2(DoubleVector v)`	Returns \|\|u-v\|\|^2
`void`	`swap(int i, int j)`	Swaps the values stored at i and j
`DoubleVector`	`times(double s)`	Multiplies a scalar
`DoubleVector`	`times(DoubleVector v)`	Multiplies another DoubleVector element by element
`DoubleVector`	`timesEquals(double s)`	Multiply a vector by a scalar in place, u = s * u
`DoubleVector`	`timesEquals(DoubleVector v)`	Multiplies another DoubleVector element by element in place
`java.lang.String`	`toString()`	Convert the DoubleVecor to a string
`java.lang.String`	`toString(int digits, boolean trailing)`	Convert the DoubleVecor to a string
`DoubleVector`	`unpivoting(IntVector index, int length)`	Returns a vector from the pivoting indices.
`boolean`	`unsorted()`	Returns true if vector not sorted

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - DoubleVector
```
public DoubleVector()
```
    Constructs a null vector.
  - DoubleVector
```
public DoubleVector(int n)
```
    Constructs an n-vector of zeros.
    
    Parameters:
    
    n - length.
  - DoubleVector
```
public DoubleVector(int n,
                    double s)
```
    Constructs a constant n-vector.
    
    Parameters:
    
    n - length.
    
    s - the scalar value used to fill the vector
  - DoubleVector
```
public DoubleVector(double[] v)
```
    Constructs a vector directly from a double array
    
    Parameters:
    
    v - the array
- Method Detail
  - set
```
public void set(int i,
                double s)
```
    Set a single element.
    
    Parameters:
    
    i - Index.
    
    s - a[i].
  - set
```
public void set(double s)
```
    Set all elements to a value
    
    Parameters:
    
    s - the value
  - set
```
public void set(int i0,
                int i1,
                double s)
```
    Set some elements to a value
    
    Parameters:
    
    i0 - the index of the first element
    
    i1 - the index of the second element
    
    s - the value
  - set
```
public void set(int i0,
                int i1,
                double[] v,
                int j0)
```
    Set some elements using a 2-D array
    
    Parameters:
    
    i0 - the index of the first element
    
    i1 - the index of the second element
    
    j0 - the index of the starting element in the 2-D array
    
    v - the values
  - set
```
public void set(DoubleVector v)
```
    Set the elements using a DoubleVector
    
    Parameters:
    
    v - the DoubleVector
  - set
```
public void set(int i0,
                int i1,
                DoubleVector v,
                int j0)
```
    Set some elements using a DoubleVector.
    
    Parameters:
    
    i0 - the index of the first element
    
    i1 - the index of the second element
    
    v - the DoubleVector
    
    j0 - the index of the starting element in the DoubleVector
  - getArray
```
public double[] getArray()
```
    Access the internal one-dimensional array.
    
    Returns:
    
    Pointer to the one-dimensional array of vector elements.
  - getArrayCopy
```
public double[] getArrayCopy()
```
    Returns a copy of the DoubleVector usng a double array.
    
    Returns:
    
    the one-dimensional array.
  - sort
```
public void sort()
```
    Sorts the array in place
  - sortWithIndex
```
public IntVector sortWithIndex()
```
    Sorts the array in place with index returned
  - sortWithIndex
```
public void sortWithIndex(int xi,
                          int xj,
                          IntVector index)
```
    Sorts the array in place with index changed
    
    Parameters:
    
    xi - first index
    
    xj - last index
    
    index - array that stores all indices
  - size
```
public int size()
```
    Gets the size of the vector.
    
    Returns:
    
    the size
  - setSize
```
public void setSize(int m)
```
    Sets the size of the vector
    
    Parameters:
    
    m - the size
  - capacity
```
public int capacity()
```
    Gets the capacity of the vector.
    
    Returns:
    
    the capacity.
  - setCapacity
```
public void setCapacity(int n)
```
    Sets the capacity of the vector
    
    Parameters:
    
    n - the capacity.
  - get
```
public double get(int i)
```
    Gets a single element.
    
    Parameters:
    
    i - Index.
    
    Returns:
    
    the value of the i-th element
  - setPlus
```
public void setPlus(int i,
                    double s)
```
    Adds a value to an element
    
    Parameters:
    
    i - the index of the element
    
    s - the value
  - setTimes
```
public void setTimes(int i,
                     double s)
```
    Multiplies a value to an element
    
    Parameters:
    
    i - the index of the element
    
    s - the value
  - addElement
```
public void addElement(double x)
```
    Adds an element into the vector
    
    Parameters:
    
    x - the value of the new element
  - square
```
public DoubleVector square()
```
    Returns the squared vector
  - sqrt
```
public DoubleVector sqrt()
```
    Returns the square-root of all the elements in the vector
  - copy
```
public DoubleVector copy()
```
    Makes a deep copy of the vector
  - clone
```
public java.lang.Object clone()
```
    Clones the DoubleVector object.
  - innerProduct
```
public double innerProduct(DoubleVector v)
```
    Returns the inner product of two DoubleVectors
    
    Parameters:
    
    v - the second DoubleVector
    
    Returns:
    
    the product
  - sign
```
public DoubleVector sign()
```
    Returns the signs of all elements in terms of -1, 0 and +1.
  - sum
```
public double sum()
```
    Returns the sum of all elements in the vector.
  - sum2
```
public double sum2()
```
    Returns the squared sum of all elements in the vector.
  - norm1
```
public double norm1()
```
    Returns the L1-norm of the vector
  - norm2
```
public double norm2()
```
    Returns the L2-norm of the vector
  - sum2
```
public double sum2(DoubleVector v)
```
    Returns ||u-v||^2
    
    Parameters:
    
    v - the second vector
  - subvector
```
public DoubleVector subvector(int i0,
                              int i1)
```
    Returns a subvector.
    
    Parameters:
    
    i0 - the index of the first element
    
    i1 - the index of the last element
    
    Returns:
    
    v[i0:i1]
  - subvector
```
public DoubleVector subvector(IntVector index)
```
    Returns a subvector.
    
    Parameters:
    
    index - stores the indices of the needed elements
    
    Returns:
    
    v[index]
  - unpivoting
```
public DoubleVector unpivoting(IntVector index,
                               int length)
```
    Returns a vector from the pivoting indices. Elements not indexed are set to zero.
    
    Parameters:
    
    index - stores the pivoting indices
    
    length - the total number of the potential elements
    
    Returns:
    
    the subvector
  - plus
```
public DoubleVector plus(double x)
```
    Adds a value to all the elements
    
    Parameters:
    
    x - the value
  - plusEquals
```
public DoubleVector plusEquals(double x)
```
    Adds a value to all the elements in place
    
    Parameters:
    
    x - the value
  - plus
```
public DoubleVector plus(DoubleVector v)
```
    Adds another vector element by element
    
    Parameters:
    
    v - the second vector
  - plusEquals
```
public DoubleVector plusEquals(DoubleVector v)
```
    Adds another vector in place element by element
    
    Parameters:
    
    v - the second vector
  - minus
```
public DoubleVector minus(double x)
```
    Subtracts a value
    
    Parameters:
    
    x - the value
  - minusEquals
```
public DoubleVector minusEquals(double x)
```
    Subtracts a value in place
    
    Parameters:
    
    x - the value
  - minus
```
public DoubleVector minus(DoubleVector v)
```
    Subtracts another DoubleVector element by element
    
    Parameters:
    
    v - the second DoubleVector
  - minusEquals
```
public DoubleVector minusEquals(DoubleVector v)
```
    Subtracts another DoubleVector element by element in place
    
    Parameters:
    
    v - the second DoubleVector
  - times
```
public DoubleVector times(double s)
```
    Multiplies a scalar
    
    Parameters:
    
    s - scalar
    
    Returns:
    
    s * v
  - timesEquals
```
public DoubleVector timesEquals(double s)
```
    Multiply a vector by a scalar in place, u = s * u
    
    Parameters:
    
    s - scalar
    
    Returns:
    
    replace u by s * u
  - times
```
public DoubleVector times(DoubleVector v)
```
    Multiplies another DoubleVector element by element
    
    Parameters:
    
    v - the second DoubleVector
  - timesEquals
```
public DoubleVector timesEquals(DoubleVector v)
```
    Multiplies another DoubleVector element by element in place
    
    Parameters:
    
    v - the second DoubleVector
  - dividedBy
```
public DoubleVector dividedBy(DoubleVector v)
```
    Divided by another DoubleVector element by element
    
    Parameters:
    
    v - the second DoubleVector
  - dividedByEquals
```
public DoubleVector dividedByEquals(DoubleVector v)
```
    Divided by another DoubleVector element by element in place
    
    Parameters:
    
    v - the second DoubleVector
  - isEmpty
```
public boolean isEmpty()
```
    Checks if it is an empty vector
  - cumulate
```
public DoubleVector cumulate()
```
    Returns a vector that stores the cumulated values of the original vector
  - cumulateInPlace
```
public DoubleVector cumulateInPlace()
```
    Cumulates the original vector in place
  - indexOfMax
```
public int indexOfMax()
```
    Returns the index of the maximum.
    If multiple maximums exist, the index of the first is returned.
  - unsorted
```
public boolean unsorted()
```
    Returns true if vector not sorted
  - cat
```
public DoubleVector cat(DoubleVector v)
```
    Combine two vectors together
    
    Parameters:
    
    v - the second vector
  - swap
```
public void swap(int i,
                 int j)
```
    Swaps the values stored at i and j
    
    Parameters:
    
    i - the index i
    
    j - the index j
  - max
```
public double max()
```
    Returns the maximum value of all elements
  - map
```
public DoubleVector map(java.lang.String className,
                        java.lang.String method)
```
    Applies a method to the vector
    
    Parameters:
    
    className - the class name
    
    method - the method
  - rev
```
public DoubleVector rev()
```
    Returns the reverse vector
  - random
```
public static DoubleVector random(int n)
```
    Returns a random vector of uniform distribution
    
    Parameters:
    
    n - the size of the vector
  - toString
```
public java.lang.String toString()
```
    Convert the DoubleVecor to a string
    
    Overrides:
    
    toString in class java.lang.Object
  - toString
```
public java.lang.String toString(int digits,
                                 boolean trailing)
```
    Convert the DoubleVecor to a string
    
    Parameters:
    
    digits - the number of digits after decimal point
    
    trailing - true if trailing zeros are to be shown
  - getRevision
```
public java.lang.String getRevision()
```
    Returns the revision string.
    
    Specified by:
    
    getRevision in interface RevisionHandler
    
    Returns:
    
    the revision
  - main
```
public static void main(java.lang.String[] args)
```

Class DoubleVector

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

DoubleVector

DoubleVector

DoubleVector

DoubleVector

Method Detail

set

set

set

set

set

set

getArray

getArrayCopy

sort

sortWithIndex

sortWithIndex

size

setSize

capacity

setCapacity

get

setPlus

setTimes

addElement

square

sqrt

copy

clone

innerProduct

sign

sum

sum2

norm1

norm2

sum2

subvector

subvector

unpivoting

plus

plusEquals

plus

plusEquals

minus

minusEquals

minus

minusEquals

times

timesEquals

times

timesEquals

dividedBy

dividedByEquals

isEmpty

cumulate

cumulateInPlace

indexOfMax

unsorted

cat

swap

max

map

rev

random

toString

toString

getRevision

main