OpenMapRealVector (Commons Math 3.0 API)

java.lang.Object
- org.apache.commons.math3.linear.RealVector
- - org.apache.commons.math3.linear.SparseRealVector
  - - org.apache.commons.math3.linear.OpenMapRealVector

All Implemented Interfaces:

Serializable
```
public class OpenMapRealVector
extends SparseRealVector
implements Serializable
```
This class implements the RealVector interface with a OpenIntToDoubleHashMap backing store.

Since:

2.0

Version:

$Id: OpenMapRealVector.java 1244107 2012-02-14 16:17:55Z erans $

See Also:
Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`protected class`	`OpenMapRealVector.OpenMapEntry` Implementation of `Entry` optimized for OpenMap.
`protected class`	`OpenMapRealVector.OpenMapSparseIterator` Iterator class to do iteration over just the non-zero elements.

Nested classes/interfaces inherited from class org.apache.commons.math3.linear.RealVector
RealVector.Entry, RealVector.SparseEntryIterator

Field Summary

Fields
Modifier and Type Field and Description

static double DEFAULT_ZERO_TOLERANCE
Default Tolerance for having a value considered zero.

Fields
Modifier and Type	Field and Description
`static double`	`DEFAULT_ZERO_TOLERANCE` Default Tolerance for having a value considered zero.

Constructor Summary

Constructors
Modifier	Constructor and Description
	`OpenMapRealVector()` Build a 0-length vector.
	`OpenMapRealVector(double[] values)` Create from an array.
	`OpenMapRealVector(Double[] values)` Create from an array.
	`OpenMapRealVector(double[] values, double epsilon)` Create from an array, specifying zero tolerance.
	`OpenMapRealVector(Double[] values, double epsilon)` Create from an array.
	`OpenMapRealVector(int dimension)` Construct a vector of zeroes.
	`OpenMapRealVector(int dimension, double epsilon)` Construct a vector of zeroes, specifying zero tolerance.
	`OpenMapRealVector(int dimension, int expectedSize)` Build a vector with known the sparseness (for advanced use only).
	`OpenMapRealVector(int dimension, int expectedSize, double epsilon)` Build a vector with known the sparseness and zero tolerance setting (for advanced use only).
	`OpenMapRealVector(OpenMapRealVector v)` Copy constructor.
`protected`	`OpenMapRealVector(OpenMapRealVector v, int resize)` Build a resized vector, for use with append.
	`OpenMapRealVector(RealVector v)` Generic copy constructor.

Method Summary

Methods
Modifier and Type	Method and Description
`OpenMapRealVector`	`add(OpenMapRealVector v)` Optimized method to add two OpenMapRealVectors.
`RealVector`	`add(RealVector v)` Compute the sum of this vector and `v`.
`OpenMapRealVector`	`append(double d)` Construct a new vector by appending a double to this vector.
`OpenMapRealVector`	`append(OpenMapRealVector v)` Optimized method to append a OpenMapRealVector.
`OpenMapRealVector`	`append(RealVector v)` Construct a new vector by appending a vector to this vector.
`OpenMapRealVector`	`copy()` Returns a (deep) copy of this vector.
`double`	`dotProduct(OpenMapRealVector v)` Optimized method to compute the dot product with an OpenMapRealVector.
`double`	`dotProduct(RealVector v)` Compute the dot product of this vector with `v`.
`OpenMapRealVector`	`ebeDivide(RealVector v)` Element-by-element division.
`OpenMapRealVector`	`ebeMultiply(RealVector v)` Element-by-element multiplication.
`boolean`	`equals(Object obj)` Implementation Note: This performs an exact comparison, and as a result it is possible for `a.subtract(b`} to be the zero vector, while `a.equals(b) == false`.
`int`	`getDimension()` Returns the size of the vector.
`double`	`getDistance(OpenMapRealVector v)` Optimized method to compute distance.
`double`	`getDistance(RealVector v)` Distance between two vectors.
`double`	`getEntry(int index)` Return the entry at the specified index.
`double`	`getL1Distance(OpenMapRealVector v)` Distance between two vectors.
`double`	`getL1Distance(RealVector v)` Distance between two vectors.
`double`	`getLInfDistance(RealVector v)` Distance between two vectors.
`double`	`getSparsity()`
`OpenMapRealVector`	`getSubVector(int index, int n)` Get a subvector from consecutive elements.
`int`	`hashCode()` Implementation Note: This works on exact values, and as a result it is possible for `a.subtract(b)` to be the zero vector, while `a.hashCode() != b.hashCode()`.
`protected boolean`	`isDefaultValue(double value)` Determine if this value is within epsilon of zero.
`boolean`	`isInfinite()` Check whether any coordinate of this vector is infinite and none are `NaN`.
`boolean`	`isNaN()` Check whether any coordinate of this vector is `NaN`.
`OpenMapRealVector`	`mapAdd(double d)` Add a value to each entry.
`OpenMapRealVector`	`mapAddToSelf(double d)` Add a value to each entry.
`RealVector`	`projection(RealVector v)` Find the orthogonal projection of this vector onto another vector.
`void`	`set(double value)` Set all elements to a single value.
`void`	`setEntry(int index, double value)` Set a single element.
`void`	`setSubVector(int index, RealVector v)` Set a sequence of consecutive elements.
`Iterator<RealVector.Entry>`	`sparseIterator()` Create a sparse iterator over the vector, which may omit some entries.
`OpenMapRealVector`	`subtract(OpenMapRealVector v)` Optimized method to subtract OpenMapRealVectors.
`RealVector`	`subtract(RealVector v)` Subtract `v` from this vector.
`double[]`	`toArray()` Convert the vector to an array of `double`s.
`void`	`unitize()` Converts this vector into a unit vector.
`OpenMapRealVector`	`unitVector()` Creates a unit vector pointing in the direction of this vector.

Methods inherited from class org.apache.commons.math3.linear.RealVector
addToEntry, checkIndex, checkVectorDimensions, checkVectorDimensions, combine, combineToSelf, cosine, getL1Norm, getLInfNorm, getMaxIndex, getMaxValue, getMinIndex, getMinValue, getNorm, iterator, map, mapDivide, mapDivideToSelf, mapMultiply, mapMultiplyToSelf, mapSubtract, mapSubtractToSelf, mapToSelf, outerProduct, unmodifiableRealVector

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DEFAULT_ZERO_TOLERANCE
```
public static final double DEFAULT_ZERO_TOLERANCE
```
    Default Tolerance for having a value considered zero.
    
    See Also:
    Constant Field Values
- Constructor Detail
  - OpenMapRealVector
```
public OpenMapRealVector()
```
    Build a 0-length vector. Zero-length vectors may be used to initialized construction of vectors by data gathering. We start with zero-length and use either the OpenMapRealVector(OpenMapRealVector, int) constructor or one of the append method (append(double), append(RealVector)) to gather data into this vector.
  - OpenMapRealVector
```
public OpenMapRealVector(int dimension)
```
    Construct a vector of zeroes.
    
    Parameters:
    dimension - Size of the vector.
  - OpenMapRealVector
```
public OpenMapRealVector(int dimension,
                 double epsilon)
```
    Construct a vector of zeroes, specifying zero tolerance.
    
    Parameters:
    dimension - Size of the vector.
    epsilon - Tolerance below which a value considered zero.
  - OpenMapRealVector
```
protected OpenMapRealVector(OpenMapRealVector v,
                 int resize)
```
    Build a resized vector, for use with append.
    
    Parameters:
    v - Original vector.
    resize - Amount to add.
  - OpenMapRealVector
```
public OpenMapRealVector(int dimension,
                 int expectedSize)
```
    Build a vector with known the sparseness (for advanced use only).
    
    Parameters:
    dimension - Size of the vector.
    expectedSize - The expected number of non-zero entries.
  - OpenMapRealVector
```
public OpenMapRealVector(int dimension,
                 int expectedSize,
                 double epsilon)
```
    Build a vector with known the sparseness and zero tolerance setting (for advanced use only).
    
    Parameters:
    dimension - Size of the vector.
    expectedSize - Expected number of non-zero entries.
    epsilon - Tolerance below which a value is considered zero.
  - OpenMapRealVector
```
public OpenMapRealVector(double[] values)
```
    Create from an array. Only non-zero entries will be stored.
    
    Parameters:
    values - Set of values to create from.
  - OpenMapRealVector
```
public OpenMapRealVector(double[] values,
                 double epsilon)
```
    Create from an array, specifying zero tolerance. Only non-zero entries will be stored.
    
    Parameters:
    values - Set of values to create from.
    epsilon - Tolerance below which a value is considered zero.
  - OpenMapRealVector
```
public OpenMapRealVector(Double[] values)
```
    Create from an array. Only non-zero entries will be stored.
    
    Parameters:
    values - The set of values to create from
  - OpenMapRealVector
```
public OpenMapRealVector(Double[] values,
                 double epsilon)
```
    Create from an array. Only non-zero entries will be stored.
    
    Parameters:
    values - Set of values to create from.
    epsilon - Tolerance below which a value is considered zero.
  - OpenMapRealVector
```
public OpenMapRealVector(OpenMapRealVector v)
```
    Copy constructor.
    
    Parameters:
    v - Instance to copy from.
  - OpenMapRealVector
```
public OpenMapRealVector(RealVector v)
```
    Generic copy constructor.
    
    Parameters:
    v - Instance to copy from.
- Method Detail
  - isDefaultValue
```
protected boolean isDefaultValue(double value)
```
    Determine if this value is within epsilon of zero.
    
    Parameters:
    value - Value to test
    
    Returns:
    true if this value is within epsilon to zero, false otherwise.
    Since:
    
    2.1
  - add
```
public RealVector add(RealVector v)
```
    Compute the sum of this vector and v. Returns a new vector. Does not change instance data.
    
    Overrides:
    
    add in class RealVector
    
    Parameters:
    v - Vector to be added.
    
    Returns:
    this + v.
  - add
```
public OpenMapRealVector add(OpenMapRealVector v)
```
    Optimized method to add two OpenMapRealVectors. It copies the larger vector, then iterates over the smaller.
    
    Parameters:
    v - Vector to add.
    
    Returns:
    the sum of this and v.
    
    Throws:
    
    DimensionMismatchException - if the dimensions do not match.
  - append
```
public OpenMapRealVector append(OpenMapRealVector v)
```
    Optimized method to append a OpenMapRealVector.
    
    Parameters:
    v - vector to append
    
    Returns:
    The result of appending v to self
  - append
```
public OpenMapRealVector append(RealVector v)
```
    Construct a new vector by appending a vector to this vector.
    
    Specified by:
    
    append in class RealVector
    
    Parameters:
    v - vector to append to this one.
    
    Returns:
    a new vector.
  - append
```
public OpenMapRealVector append(double d)
```
    Construct a new vector by appending a double to this vector.
    
    Specified by:
    
    append in class RealVector
    
    Parameters:
    d - double to append.
    
    Returns:
    a new vector.
  - copy
```
public OpenMapRealVector copy()
```
    Returns a (deep) copy of this vector.
    
    Specified by:
    
    copy in class RealVector
    
    Returns:
    a vector copy.
    Since:
    
    2.1
  - dotProduct
```
public double dotProduct(OpenMapRealVector v)
```
    Optimized method to compute the dot product with an OpenMapRealVector. It iterates over the smallest of the two.
    
    Parameters:
    v - Cector to compute the dot product with.
    
    Returns:
    the dot product of this and v.
    
    Throws:
    
    DimensionMismatchException - if the dimensions do not match.
  - dotProduct
```
public double dotProduct(RealVector v)
```
    Compute the dot product of this vector with v.
    
    Overrides:
    
    dotProduct in class RealVector
    
    Parameters:
    v - Vector with which dot product should be computed
    
    Returns:
    the scalar dot product between this instance and v.
  - ebeDivide
```
public OpenMapRealVector ebeDivide(RealVector v)
```
    Element-by-element division.
    
    Specified by:
    
    ebeDivide in class RealVector
    
    Parameters:
    v - Vector by which instance elements must be divided.
    
    Returns:
    a vector containing this[i] / v[i] for all i.
  - ebeMultiply
```
public OpenMapRealVector ebeMultiply(RealVector v)
```
    Element-by-element multiplication.
    
    Specified by:
    
    ebeMultiply in class RealVector
    
    Parameters:
    v - Vector by which instance elements must be multiplied
    
    Returns:
    a vector containing this[i] * v[i] for all i.
  - getSubVector
```
public OpenMapRealVector getSubVector(int index,
                             int n)
```
    Get a subvector from consecutive elements.
    
    Specified by:
    
    getSubVector in class RealVector
    
    Parameters:
    index - index of first element.
    n - number of elements to be retrieved.
    
    Returns:
    a vector containing n elements.
  - getDimension
```
public int getDimension()
```
    Returns the size of the vector.
    
    Specified by:
    
    getDimension in class RealVector
    
    Returns:
    the size of this vector.
  - getDistance
```
public double getDistance(OpenMapRealVector v)
```
    Optimized method to compute distance.
    
    Parameters:
    v - Vector to compute distance to.
    
    Returns:
    the distance from this and v.
    
    Throws:
    
    DimensionMismatchException - if the dimensions do not match.
  - getDistance
```
public double getDistance(RealVector v)
```
    Distance between two vectors.
    This method computes the distance consistent with the L₂ norm, i.e. the square root of the sum of element differences, or Euclidian distance.
    
    Overrides:
    
    getDistance in class RealVector
    
    Parameters:
    v - Vector to which distance is requested.
    
    Returns:
    the distance between two vectors.
    See Also:
    RealVector.getL1Distance(RealVector), RealVector.getLInfDistance(RealVector), RealVector.getNorm()
  - getEntry
```
public double getEntry(int index)
```
    Return the entry at the specified index.
    
    Specified by:
    
    getEntry in class RealVector
    
    Parameters:
    index - Index location of entry to be fetched.
    
    Returns:
    the vector entry at index.
    See Also:
    RealVector.setEntry(int, double)
  - getL1Distance
```
public double getL1Distance(OpenMapRealVector v)
```
    Distance between two vectors. This method computes the distance consistent with L₁ norm, i.e. the sum of the absolute values of elements differences.
    
    Parameters:
    v - Vector to which distance is requested.
    
    Returns:
    distance between this vector and v.
  - getL1Distance
```
public double getL1Distance(RealVector v)
```
    Distance between two vectors.
    This method computes the distance consistent with L₁ norm, i.e. the sum of the absolute values of the elements differences.
    
    Overrides:
    
    getL1Distance in class RealVector
    
    Parameters:
    v - Vector to which distance is requested.
    
    Returns:
    the distance between two vectors.
  - getLInfDistance
```
public double getLInfDistance(RealVector v)
```
    Distance between two vectors.
    This method computes the distance consistent with L_∞ norm, i.e. the max of the absolute values of element differences.
    
    Overrides:
    
    getLInfDistance in class RealVector
    
    Parameters:
    v - Vector to which distance is requested.
    
    Returns:
    the distance between two vectors.
    See Also:
    RealVector.getDistance(RealVector), RealVector.getL1Distance(RealVector), RealVector.getLInfNorm()
  - isInfinite
```
public boolean isInfinite()
```
    Check whether any coordinate of this vector is infinite and none are NaN.
    
    Specified by:
    
    isInfinite in class RealVector
    
    Returns:
    true if any coordinate of this vector is infinite and none are NaN, false otherwise.
  - isNaN
```
public boolean isNaN()
```
    Check whether any coordinate of this vector is NaN.
    
    Specified by:
    
    isNaN in class RealVector
    
    Returns:
    true if any coordinate of this vector is NaN, false otherwise.
  - mapAdd
```
public OpenMapRealVector mapAdd(double d)
```
    Add a value to each entry. Returns a new vector. Does not change instance data.
    
    Overrides:
    
    mapAdd in class RealVector
    
    Parameters:
    d - Value to be added to each entry.
    
    Returns:
    this + d.
  - mapAddToSelf
```
public OpenMapRealVector mapAddToSelf(double d)
```
    Add a value to each entry. The instance is changed in-place.
    
    Overrides:
    
    mapAddToSelf in class RealVector
    
    Parameters:
    d - Value to be added to each entry.
    
    Returns:
    this.
  - projection
```
public RealVector projection(RealVector v)
```
    Find the orthogonal projection of this vector onto another vector.
    
    Specified by:
    
    projection in class RealVector
    
    Parameters:
    v - vector onto which instance must be projected.
    
    Returns:
    projection of the instance onto v.
  - setEntry
```
public void setEntry(int index,
            double value)
```
    Set a single element.
    
    Specified by:
    
    setEntry in class RealVector
    
    Parameters:
    index - element index.
    value - new value for the element.
    See Also:
    RealVector.getEntry(int)
  - setSubVector
```
public void setSubVector(int index,
                RealVector v)
```
    Set a sequence of consecutive elements.
    
    Specified by:
    
    setSubVector in class RealVector
    
    Parameters:
    index - index of first element to be set.
    v - vector containing the values to set.
  - set
```
public void set(double value)
```
    Set all elements to a single value.
    
    Overrides:
    
    set in class RealVector
    
    Parameters:
    value - Single value to set for all elements.
  - subtract
```
public OpenMapRealVector subtract(OpenMapRealVector v)
```
    Optimized method to subtract OpenMapRealVectors.
    
    Parameters:
    v - Vector to subtract from this.
    
    Returns:
    the difference of this and v.
    
    Throws:
    
    DimensionMismatchException - if the dimensions do not match.
  - subtract
```
public RealVector subtract(RealVector v)
```
    Subtract v from this vector. Returns a new vector. Does not change instance data.
    
    Overrides:
    
    subtract in class RealVector
    
    Parameters:
    v - Vector to be subtracted.
    
    Returns:
    this - v.
  - unitVector
```
public OpenMapRealVector unitVector()
```
    Creates a unit vector pointing in the direction of this vector. The instance is not changed by this method.
    
    Overrides:
    
    unitVector in class RealVector
    
    Returns:
    a unit vector pointing in direction of this vector.
  - unitize
```
public void unitize()
```
    Converts this vector into a unit vector. The instance itself is changed by this method.
    
    Overrides:
    
    unitize in class RealVector
  - toArray
```
public double[] toArray()
```
    Convert the vector to an array of doubles. The array is independent from this vector data: the elements are copied.
    
    Overrides:
    
    toArray in class RealVector
    
    Returns:
    an array containing a copy of the vector elements.
  - hashCode
```
public int hashCode()
```
    Implementation Note: This works on exact values, and as a result it is possible for a.subtract(b) to be the zero vector, while a.hashCode() != b.hashCode().
    
    Overrides:
    
    hashCode in class Object
  - equals
```
public boolean equals(Object obj)
```
    Implementation Note: This performs an exact comparison, and as a result it is possible for a.subtract(b} to be the zero vector, while a.equals(b) == false.
    
    Overrides:
    
    equals in class Object
  - getSparsity
```
public double getSparsity()
```
    Returns:
    the percentage of none zero elements as a decimal percent.
    Since:
    
    2.2
  - sparseIterator
```
public Iterator<RealVector.Entry> sparseIterator()
```
    Create a sparse iterator over the vector, which may omit some entries. Specialized implementations may choose to not iterate over all dimensions, either because those values are unset, or are equal to defaultValue(), or are small enough to be ignored for the purposes of iteration. No guarantees are made about order of iteration. In dense implementations, this method will often delegate to RealVector.iterator().
    
    Overrides:
    
    sparseIterator in class RealVector
    
    Returns:
    a sparse iterator.

Class OpenMapRealVector

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.commons.math3.linear.RealVector

Field Summary

Constructor Summary

Method Summary

Methods inherited from class org.apache.commons.math3.linear.RealVector

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_ZERO_TOLERANCE

Constructor Detail

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

OpenMapRealVector

Method Detail

isDefaultValue

add

add

append

append

append

copy

dotProduct

dotProduct

ebeDivide

ebeMultiply

getSubVector

getDimension

getDistance

getDistance

getEntry

getL1Distance

getL1Distance

getLInfDistance

isInfinite

isNaN

mapAdd

mapAddToSelf

projection

setEntry

setSubVector

set

subtract

subtract

unitVector

unitize

toArray

hashCode

equals

getSparsity

sparseIterator