de.lmu.ifi.dbs.elki.math.linearalgebra
Class Vector

java.lang.Object
  de.lmu.ifi.dbs.elki.math.linearalgebra.Matrix
      de.lmu.ifi.dbs.elki.math.linearalgebra.Vector

All Implemented Interfaces:

Serializable, Cloneable

public class Vector
extends Matrix

Provides a vector object that encapsulates an m x 1 - matrix object.

Author:

Elke Achtert

See Also:

Serialized Form

Field Summary

Fields inherited from class de.lmu.ifi.dbs.elki.math.linearalgebra.Matrix

DELTA

Constructor Summary

Vector(double[] values)
Construct a vector from a given array.

Vector(int m)
Provides an m x 1 vector.

Method Summary

private void	checkDimensions(Vector v) Check if this.getDimensionality() == v.getDimensionality().
Vector	copy() Returns a copy of this vector.
double	get(int i) Returns the value at the specified row.
int	getDimensionality() Returns the dimensionality of this vector.
Vector	inverseVector() Inverts every element of the vector.
double	length() Returns the length of this vector.
Vector	minus(Vector v) Returns this vector minus the specified vector v.
void	normalize() Normalizes this vector to the length of 1.0.
Vector	plus(Vector v) Returns a new vector which is the result of this vector plus the specified vector.
static Vector	randomNormalizedVector(int dimensionality) Returns a randomly created vector of length 1.0
double	scalarProduct(Vector v) Returns the scalar product of this vector and the specified vector v.
void	set(int i, double value) Sets the value at the specified row.
Vector	sqrtVector() Square roots every element of the vector.
Vector	times(double s) Returns a new vector which is the result of this vector multiplied by the specified scalar.
String	toString() Returns a string representation of this vector.
String	toString(NumberFormat nf) Returns a string representation of this vector.
String	toStringNoWhitespace() Returns a string representation of this vector without adding extra whitespace
static Vector	unitVector(int dimensionality, int i) Returns the ith unit vector of the specified dimensionality.

Methods inherited from class de.lmu.ifi.dbs.elki.math.linearalgebra.Matrix

almostEquals, almostEquals, angle, appendColumns, arrayLeftDivide, arrayLeftDivideEquals, arrayRightDivide, arrayRightDivideEquals, arrayTimes, arrayTimesEquals, cheatToAvoidSingularity, chol, clone, completeBasis, completeToOrthonormalBasis, cond, constructWithCopy, det, diagonal, diagonal, dimensionInfo, distanceCov, eig, equals, euclideanNorm, exactGaussJordanElimination, get, getArray, getArrayCopy, getColumn, getColumnDimensionality, getColumnPackedCopy, getColumnVector, getDiagonal, getMatrix, getMatrix, getMatrix, getMatrix, getRow, getRowDimensionality, getRowPackedCopy, getRowVector, hashCode, identity, increment, inverse, isSymmetric, linearlyIndependent, lu, minus, minusEquals, norm1, norm2, normalizeColumns, normF, normInf, orthonormalize, plus, plusEquals, print, print, print, print, projection, qr, random, rank, read, scalarProduct, scaleColumn, scaleColumns, set, setColumn, setMatrix, setMatrix, setMatrix, setMatrix, solve, solveTranspose, svd, swapColumn, swapRow, times, timesEquals, toString, toString, toString, trace, transpose, uminus, unitMatrix, zeroMatrix

Methods inherited from class java.lang.Object

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

Constructor Detail

Vector

public Vector(double[] values)

Construct a vector from a given array.

Parameters:

values - array of doubles

Vector

public Vector(int m)

Provides an m x 1 vector.

Parameters:

m - the number of rows

Method Detail

get

public double get(int i)

Returns the value at the specified row.

Parameters:

i - the row index

Returns:

the value at row i

set

public void set(int i,
                double value)

Sets the value at the specified row.

Parameters:

i - the row index

value - the value to be set

inverseVector

public Vector inverseVector()

Inverts every element of the vector.

Returns:

the resulting vector

sqrtVector

public Vector sqrtVector()

Square roots every element of the vector.

Returns:

the resulting vector

minus

public Vector minus(Vector v)

Returns this vector minus the specified vector v.

Parameters:

v - the vector to be subtracted from this vector

Returns:

this vector minus the specified vector v

scalarProduct

public double scalarProduct(Vector v)

Returns the scalar product of this vector and the specified vector v.

Parameters:

v - the vector

Returns:

double the scalar product of this vector and v

length

public double length()

Returns the length of this vector.

Returns:

the length of this vector

getDimensionality

public int getDimensionality()

Returns the dimensionality of this vector.

Returns:

the dimensionality of this vector

normalize

public void normalize()

Normalizes this vector to the length of 1.0.

plus

public Vector plus(Vector v)

Returns a new vector which is the result of this vector plus the specified vector.

Parameters:

v - the vector to be added

Returns:

the resulting vector

times

public Vector times(double s)

Returns a new vector which is the result of this vector multiplied by the specified scalar.

Overrides:

times in class Matrix

Parameters:

s - the scalar to be multiplied

Returns:

the resulting vector

randomNormalizedVector

public static Vector randomNormalizedVector(int dimensionality)

Returns a randomly created vector of length 1.0

Parameters:

dimensionality -

Returns:

the dimensionality of the vector

unitVector

public static Vector unitVector(int dimensionality,
                                int i)

Returns the ith unit vector of the specified dimensionality.

Parameters:

dimensionality - the dimensionality of the vector

i - the index

Returns:

the ith unit vector of the specified dimensionality

copy

public Vector copy()

Returns a copy of this vector.

Overrides:

copy in class Matrix

Returns:

a copy of this vector

toStringNoWhitespace

public String toStringNoWhitespace()

Returns a string representation of this vector without adding extra whitespace

Returns:

a string representation of this vector.

toString

public String toString()

Returns a string representation of this vector.

Overrides:

toString in class Matrix

Returns:

a string representation of this vector.

toString

public String toString(NumberFormat nf)

Returns a string representation of this vector.

Overrides:

toString in class Matrix

Parameters:

nf - a NumberFormat to specify the output precision

Returns:

a string representation of this vector.

checkDimensions

private void checkDimensions(Vector v)

Check if this.getDimensionality() == v.getDimensionality().

Throws:

IllegalArgumentException - if the dimensions do not agree