org.apache.commons.math3.linear

Class SparseFieldVector<T extends FieldElement<T>>

java.lang.Object

org.apache.commons.math3.linear.SparseFieldVector<T>

Type Parameters:

T - the type of the field elements

All Implemented Interfaces:

java.io.Serializable, FieldVector<T>

public class SparseFieldVector<T extends FieldElement<T>>
extends java.lang.Object
implements FieldVector<T>, java.io.Serializable

This class implements the FieldVector interface with a OpenIntToFieldHashMap backing store.

Caveat: This implementation assumes that, for any x, the equality x * 0d == 0d holds. But it is is not true for NaN. Moreover, zero entries will lose their sign. Some operations (that involve NaN and/or infinities) may thus give incorrect results.

Since:

2.0

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
SparseFieldVector(Field<T> field) Build a 0-length vector.
SparseFieldVector(Field<T> field, int dimension) Construct a vector of zeroes.
SparseFieldVector(Field<T> field, int dimension, int expectedSize) Build a vector with known the sparseness (for advanced use only).
SparseFieldVector(Field<T> field, T[] values) Create from a Field array.
SparseFieldVector(SparseFieldVector<T> v) Copy constructor.

Method Summary

Modifier and Type	Method and Description
FieldVector<T>	add(FieldVector<T> v) Compute the sum of this and v.
FieldVector<T>	add(SparseFieldVector<T> v) Optimized method to add sparse vectors.
FieldVector<T>	append(FieldVector<T> v) Construct a vector by appending a vector to this vector.
FieldVector<T>	append(SparseFieldVector<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>	copy() Returns a (deep) copy of this.
T	dotProduct(FieldVector<T> v) Compute the dot product.
FieldVector<T>	ebeDivide(FieldVector<T> v) Element-by-element division.
FieldVector<T>	ebeMultiply(FieldVector<T> v) Element-by-element multiplication.
boolean	equals(java.lang.Object obj)
T[]	getData() Deprecated. as of 3.1, to be removed in 4.0. Please use the toArray() method instead.
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.
int	hashCode()
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(SparseFieldVector<T> v) Optimized method to compute outer product when both vectors are sparse.
FieldVector<T>	projection(FieldVector<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.
FieldVector<T>	subtract(FieldVector<T> v) Compute this minus v.
SparseFieldVector<T>	subtract(SparseFieldVector<T> v) Optimized method to compute this minus v.
T[]	toArray() Convert the vector to a T array.
T	walkInDefaultOrder(FieldVectorChangingVisitor<T> visitor) Visits (and possibly alters) all entries of this vector in default order (increasing index).
T	walkInDefaultOrder(FieldVectorChangingVisitor<T> visitor, int start, int end) Visits (and possibly alters) some entries of this vector in default order (increasing index).
T	walkInDefaultOrder(FieldVectorPreservingVisitor<T> visitor) Visits (but does not alter) all entries of this vector in default order (increasing index).
T	walkInDefaultOrder(FieldVectorPreservingVisitor<T> visitor, int start, int end) Visits (but does not alter) some entries of this vector in default order (increasing index).
T	walkInOptimizedOrder(FieldVectorChangingVisitor<T> visitor) Visits (and possibly alters) all entries of this vector in optimized order.
T	walkInOptimizedOrder(FieldVectorChangingVisitor<T> visitor, int start, int end) Visits (and possibly change) some entries of this vector in optimized order.
T	walkInOptimizedOrder(FieldVectorPreservingVisitor<T> visitor) Visits (but does not alter) all entries of this vector in optimized order.
T	walkInOptimizedOrder(FieldVectorPreservingVisitor<T> visitor, int start, int end) Visits (but does not alter) some entries of this vector in optimized order.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SparseFieldVector

public SparseFieldVector(Field<T> field)

Build a 0-length vector. Zero-length vectors may be used to initialize construction of vectors by data gathering. We start with zero-length and use either the SparseFieldVector(SparseFieldVector, int) constructor or one of the append method (append(FieldVector) or append(SparseFieldVector)) to gather data into this vector.

Parameters:

field - Field to which the elements belong.

SparseFieldVector

public SparseFieldVector(Field<T> field,
                         int dimension)

Construct a vector of zeroes.

Parameters:

field - Field to which the elements belong.

dimension - Size of the vector.

SparseFieldVector

public SparseFieldVector(Field<T> field,
                         int dimension,
                         int expectedSize)

Build a vector with known the sparseness (for advanced use only).

Parameters:

field - Field to which the elements belong.

dimension - Size of the vector.

expectedSize - Expected number of non-zero entries.

SparseFieldVector

public SparseFieldVector(Field<T> field,
                         T[] values)
                  throws NullArgumentException

Create from a Field array. Only non-zero entries will be stored.

Parameters:

field - Field to which the elements belong.

values - Set of values to create from.

Throws:

NullArgumentException - if values is null

SparseFieldVector

public SparseFieldVector(SparseFieldVector<T> v)

Copy constructor.

Parameters:

v - Instance to copy.

Method Detail

add

public FieldVector<T> add(SparseFieldVector<T> v)
                   throws DimensionMismatchException

Optimized method to add sparse vectors.

Parameters:

v - Vector to add.

Returns:

this + v.

Throws:

DimensionMismatchException - if v is not the same size as this.

append

public FieldVector<T> append(SparseFieldVector<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

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

Construct a vector by appending a vector to this vector.

Specified by:

append in interface FieldVector<T extends FieldElement<T>>

Parameters:

v - vector to append to this one.

Returns:

a new vector

append

public FieldVector<T> append(T d)
                      throws NullArgumentException

Construct a vector by appending a T to this vector.

Specified by:

append in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - T to append.

Returns:

a new vector

Throws:

NullArgumentException - if d is null

copy

public FieldVector<T> copy()

Returns a (deep) copy of this.

Specified by:

copy in interface FieldVector<T extends FieldElement<T>>

Returns:

vector copy

dotProduct

public T dotProduct(FieldVector<T> v)
             throws DimensionMismatchException

Compute the dot product.

Specified by:

dotProduct in interface FieldVector<T extends FieldElement<T>>

Parameters:

v - vector with which dot product should be computed

Returns:

the scalar dot product of this and v

Throws:

DimensionMismatchException - if v is not the same size as this

ebeDivide

public FieldVector<T> ebeDivide(FieldVector<T> v)
                         throws DimensionMismatchException,
                                MathArithmeticException

Element-by-element division.

Specified by:

ebeDivide in interface FieldVector<T extends FieldElement<T>>

Parameters:

v - vector by which instance elements must be divided

Returns:

a vector containing this[i] / v[i] for all i

Throws:

DimensionMismatchException - if v is not the same size as this

MathArithmeticException - if one entry of v is zero.

ebeMultiply

public FieldVector<T> ebeMultiply(FieldVector<T> v)
                           throws DimensionMismatchException

Element-by-element multiplication.

Specified by:

ebeMultiply in interface FieldVector<T extends FieldElement<T>>

Parameters:

v - vector by which instance elements must be multiplied

Returns:

a vector containing this[i] * v[i] for all i

Throws:

DimensionMismatchException - if v is not the same size as this

getData

@Deprecated
public T[] getData()

Deprecated. as of 3.1, to be removed in 4.0. Please use the toArray() method instead.

Returns vector entries as a T array.

Specified by:

getData in interface FieldVector<T extends FieldElement<T>>

Returns:

T array of entries

getDimension

public int getDimension()

Returns the size of the vector.

Specified by:

getDimension in interface FieldVector<T extends FieldElement<T>>

Returns:

size

getEntry

public T getEntry(int index)
           throws OutOfRangeException

Returns the entry in the specified index.

Specified by:

getEntry in interface FieldVector<T extends FieldElement<T>>

Parameters:

index - Index location of entry to be fetched.

Returns:

the vector entry at index.

Throws:

OutOfRangeException - if the index is not valid.

See Also:

FieldVector.setEntry(int, FieldElement)

getField

public Field<T> getField()

Get the type of field elements of the vector.

Specified by:

getField in interface FieldVector<T extends FieldElement<T>>

Returns:

type of field elements of the vector

getSubVector

public FieldVector<T> getSubVector(int index,
                                   int n)
                            throws OutOfRangeException,
                                   NotPositiveException

Get a subvector from consecutive elements.

Specified by:

getSubVector in interface FieldVector<T extends FieldElement<T>>

Parameters:

index - index of first element.

n - number of elements to be retrieved.

Returns:

a vector containing n elements.

Throws:

OutOfRangeException - if the index is not valid.

NotPositiveException - if the number of elements if not positive.

mapAdd

public FieldVector<T> mapAdd(T d)
                      throws NullArgumentException

Map an addition operation to each entry.

Specified by:

mapAdd in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - value to be added to each entry

Returns:

this + d

Throws:

NullArgumentException - if d is null.

mapAddToSelf

public FieldVector<T> mapAddToSelf(T d)
                            throws NullArgumentException

Map an addition operation to each entry.

The instance is changed by this method.

Specified by:

mapAddToSelf in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - value to be added to each entry

Returns:

for convenience, return this

Throws:

NullArgumentException - if d is null.

mapDivide

public FieldVector<T> mapDivide(T d)
                         throws NullArgumentException,
                                MathArithmeticException

Map a division operation to each entry.

Specified by:

mapDivide in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - value to divide all entries by

Returns:

this / d

Throws:

NullArgumentException - if d is null.

MathArithmeticException - if d is zero.

mapDivideToSelf

public FieldVector<T> mapDivideToSelf(T d)
                               throws NullArgumentException,
                                      MathArithmeticException

Map a division operation to each entry.

The instance is changed by this method.

Specified by:

mapDivideToSelf in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - value to divide all entries by

Returns:

for convenience, return this

Throws:

NullArgumentException - if d is null.

MathArithmeticException - if d is zero.

mapInv

public FieldVector<T> mapInv()
                      throws MathArithmeticException

Map the 1/x function to each entry.

Specified by:

mapInv in interface FieldVector<T extends FieldElement<T>>

Returns:

a vector containing the result of applying the function to each entry.

Throws:

MathArithmeticException - if one of the entries is zero.

mapInvToSelf

public FieldVector<T> mapInvToSelf()
                            throws MathArithmeticException

Map the 1/x function to each entry.

The instance is changed by this method.

Specified by:

mapInvToSelf in interface FieldVector<T extends FieldElement<T>>

Returns:

for convenience, return this

Throws:

MathArithmeticException - if one of the entries is zero.

mapMultiply

public FieldVector<T> mapMultiply(T d)
                           throws NullArgumentException

Map a multiplication operation to each entry.

Specified by:

mapMultiply in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - value to multiply all entries by

Returns:

this * d

Throws:

NullArgumentException - if d is null.

mapMultiplyToSelf

public FieldVector<T> mapMultiplyToSelf(T d)
                                 throws NullArgumentException

Map a multiplication operation to each entry.

The instance is changed by this method.

Specified by:

mapMultiplyToSelf in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - value to multiply all entries by

Returns:

for convenience, return this

Throws:

NullArgumentException - if d is null.

mapSubtract

public FieldVector<T> mapSubtract(T d)
                           throws NullArgumentException

Map a subtraction operation to each entry.

Specified by:

mapSubtract in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - value to be subtracted to each entry

Returns:

this - d

Throws:

NullArgumentException - if d is null

mapSubtractToSelf

public FieldVector<T> mapSubtractToSelf(T d)
                                 throws NullArgumentException

Map a subtraction operation to each entry.

The instance is changed by this method.

Specified by:

mapSubtractToSelf in interface FieldVector<T extends FieldElement<T>>

Parameters:

d - value to be subtracted to each entry

Returns:

for convenience, return this

Throws:

NullArgumentException - if d is null

outerProduct

public FieldMatrix<T> outerProduct(SparseFieldVector<T> v)

Optimized method to compute outer product when both vectors are sparse.

Parameters:

v - vector with which outer product should be computed

Returns:

the matrix outer product between instance and v

outerProduct

public FieldMatrix<T> outerProduct(FieldVector<T> v)

Compute the outer product.

Specified by:

outerProduct in interface FieldVector<T extends FieldElement<T>>

Parameters:

v - vector with which outer product should be computed

Returns:

the matrix outer product between instance and v

projection

public FieldVector<T> projection(FieldVector<T> v)
                          throws DimensionMismatchException,
                                 MathArithmeticException

Find the orthogonal projection of this vector onto another vector.

Specified by:

projection in interface FieldVector<T extends FieldElement<T>>

Parameters:

v - vector onto which this must be projected

Returns:

projection of this onto v

Throws:

DimensionMismatchException - if v is not the same size as this

MathArithmeticException - if v is the null vector.

set

public void set(T value)

Set all elements to a single value.

Specified by:

set in interface FieldVector<T extends FieldElement<T>>

Parameters:

value - single value to set for all elements

Throws:

NullArgumentException - if value is null

setEntry

public void setEntry(int index,
                     T value)
              throws NullArgumentException,
                     OutOfRangeException

Set a single element.

Specified by:

setEntry in interface FieldVector<T extends FieldElement<T>>

Parameters:

index - element index.

value - new value for the element.

Throws:

NullArgumentException - if value is null

OutOfRangeException - if the index is not valid.

See Also:

FieldVector.getEntry(int)

setSubVector

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

Set a set of consecutive elements.

Specified by:

setSubVector in interface FieldVector<T extends FieldElement<T>>

Parameters:

index - index of first element to be set.

v - vector containing the values to set.

Throws:

OutOfRangeException - if the index is not valid.

subtract

public SparseFieldVector<T> subtract(SparseFieldVector<T> v)
                              throws DimensionMismatchException

Optimized method to compute this minus v.

Parameters:

v - vector to be subtracted

Returns:

this - v

Throws:

DimensionMismatchException - if v is not the same size as this.

subtract

public FieldVector<T> subtract(FieldVector<T> v)
                        throws DimensionMismatchException

Compute this minus v.

Specified by:

subtract in interface FieldVector<T extends FieldElement<T>>

Parameters:

v - vector to be subtracted

Returns:

this - v

Throws:

DimensionMismatchException - if v is not the same size as this

toArray

public T[] toArray()

Convert the vector to a T array.

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

Specified by:

toArray in interface FieldVector<T extends FieldElement<T>>

Returns:

array containing a copy of vector elements

add

public FieldVector<T> add(FieldVector<T> v)
                   throws DimensionMismatchException

Compute the sum of this and v.

Specified by:

add in interface FieldVector<T extends FieldElement<T>>

Parameters:

v - vector to be added

Returns:

this + v

Throws:

DimensionMismatchException - if v is not the same size as this

walkInDefaultOrder

public T walkInDefaultOrder(FieldVectorPreservingVisitor<T> visitor)

Visits (but does not alter) all entries of this vector in default order (increasing index).

Parameters:

visitor - the visitor to be used to process the entries of this vector

Returns:

the value returned by FieldVectorPreservingVisitor.end() at the end of the walk

Since:

3.3

walkInDefaultOrder

public T walkInDefaultOrder(FieldVectorPreservingVisitor<T> visitor,
                            int start,
                            int end)
                     throws NumberIsTooSmallException,
                            OutOfRangeException

Visits (but does not alter) some entries of this vector in default order (increasing index).

Parameters:

visitor - visitor to be used to process the entries of this vector

start - the index of the first entry to be visited

end - the index of the last entry to be visited (inclusive)

Returns:

the value returned by FieldVectorPreservingVisitor.end() at the end of the walk

Throws:

NumberIsTooSmallException - if end < start.

OutOfRangeException - if the indices are not valid.

Since:

3.3

walkInOptimizedOrder

public T walkInOptimizedOrder(FieldVectorPreservingVisitor<T> visitor)

Visits (but does not alter) all entries of this vector in optimized order. The order in which the entries are visited is selected so as to lead to the most efficient implementation; it might depend on the concrete implementation of this abstract class.

Parameters:

visitor - the visitor to be used to process the entries of this vector

Returns:

the value returned by FieldVectorPreservingVisitor.end() at the end of the walk

Since:

3.3

walkInOptimizedOrder

public T walkInOptimizedOrder(FieldVectorPreservingVisitor<T> visitor,
                              int start,
                              int end)
                       throws NumberIsTooSmallException,
                              OutOfRangeException

Visits (but does not alter) some entries of this vector in optimized order. The order in which the entries are visited is selected so as to lead to the most efficient implementation; it might depend on the concrete implementation of this abstract class.

Parameters:

visitor - visitor to be used to process the entries of this vector

start - the index of the first entry to be visited

end - the index of the last entry to be visited (inclusive)

Returns:

the value returned by FieldVectorPreservingVisitor.end() at the end of the walk

Throws:

NumberIsTooSmallException - if end < start.

OutOfRangeException - if the indices are not valid.

Since:

3.3

walkInDefaultOrder

public T walkInDefaultOrder(FieldVectorChangingVisitor<T> visitor)

Visits (and possibly alters) all entries of this vector in default order (increasing index).

Parameters:

visitor - the visitor to be used to process and modify the entries of this vector

Returns:

the value returned by FieldVectorChangingVisitor.end() at the end of the walk

Since:

3.3

walkInDefaultOrder

public T walkInDefaultOrder(FieldVectorChangingVisitor<T> visitor,
                            int start,
                            int end)
                     throws NumberIsTooSmallException,
                            OutOfRangeException

Visits (and possibly alters) some entries of this vector in default order (increasing index).

Parameters:

visitor - visitor to be used to process the entries of this vector

start - the index of the first entry to be visited

end - the index of the last entry to be visited (inclusive)

Returns:

the value returned by FieldVectorChangingVisitor.end() at the end of the walk

Throws:

NumberIsTooSmallException - if end < start.

OutOfRangeException - if the indices are not valid.

Since:

3.3

walkInOptimizedOrder

public T walkInOptimizedOrder(FieldVectorChangingVisitor<T> visitor)

Visits (and possibly alters) all entries of this vector in optimized order. The order in which the entries are visited is selected so as to lead to the most efficient implementation; it might depend on the concrete implementation of this abstract class.

Parameters:

visitor - the visitor to be used to process the entries of this vector

Returns:

the value returned by FieldVectorChangingVisitor.end() at the end of the walk

Since:

3.3

walkInOptimizedOrder

public T walkInOptimizedOrder(FieldVectorChangingVisitor<T> visitor,
                              int start,
                              int end)
                       throws NumberIsTooSmallException,
                              OutOfRangeException

Visits (and possibly change) some entries of this vector in optimized order. The order in which the entries are visited is selected so as to lead to the most efficient implementation; it might depend on the concrete implementation of this abstract class.

Parameters:

visitor - visitor to be used to process the entries of this vector

start - the index of the first entry to be visited

end - the index of the last entry to be visited (inclusive)

Returns:

the value returned by FieldVectorChangingVisitor.end() at the end of the walk

Throws:

NumberIsTooSmallException - if end < start.

OutOfRangeException - if the indices are not valid.

Since:

3.3

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object