Class OpenMapRealVector
- All Implemented Interfaces:
Serializable
RealVector
interface with a
OpenIntToDoubleHashMap
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, like multiplications, divisions or
functions mapping.
- See Also:
-
Nested Class Summary
Modifier and TypeClassDescriptionprotected class
Implementation ofEntry
optimized for OpenMap.protected class
Iterator class to do iteration over just the non-zero elements.Nested classes/interfaces inherited from class org.hipparchus.linear.RealVector
RealVector.Entry, RealVector.SparseEntryIterator
-
Field Summary
Modifier and TypeFieldDescriptionstatic final double
Default Tolerance for having a value considered zero. -
Constructor Summary
ModifierConstructorDescriptionBuild a 0-length vector.OpenMapRealVector
(double[] values) Create from an array.OpenMapRealVector
(double[] values, double epsilon) Create from an array, specifying zero tolerance.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
(Double[] values) Create from an array.OpenMapRealVector
(Double[] values, double epsilon) Create from an array.Copy constructor.protected
OpenMapRealVector
(OpenMapRealVector v, int resize) Build a resized vector, for use with append.Generic copy constructor. -
Method Summary
Modifier and TypeMethodDescriptionOptimized method to add two OpenMapRealVectors.add
(RealVector v) Compute the sum of this vector andv
.append
(double d) Construct a new vector by appending a double to this vector.Optimized method to append a OpenMapRealVector.append
(RealVector v) Construct a new vector by appending a vector to this vector.copy()
Returns a (deep) copy of this vector.Element-by-element division.Element-by-element multiplication.boolean
Test for the equality of two real vectors.int
Returns the size of the vector.double
Optimized method to compute distance.double
Distance between two vectors.double
getEntry
(int index) Return the entry at the specified index.double
Distance between two vectors.double
Distance between two vectors.double
Distance between two vectors.double
Get percentage of none zero elements as a decimal percent.getSubVector
(int index, int n) Get a subvector from consecutive elements.int
hashCode()
.protected boolean
isDefaultValue
(double value) Determine if this value is within epsilon of zero.boolean
Check whether any coordinate of this vector is infinite and none areNaN
.boolean
isNaN()
Check whether any coordinate of this vector isNaN
.mapAdd
(double d) Add a value to each entry.mapAddToSelf
(double d) Add a value to each entry.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.Create a sparse iterator over the vector, which may omit some entries.Optimized method to subtract OpenMapRealVectors.Subtractv
from this vector.double[]
toArray()
Convert the vector to an array ofdouble
s.void
unitize()
Converts this vector into a unit vector.Creates a unit vector pointing in the direction of this vector.Methods inherited from class org.hipparchus.linear.RealVector
addToEntry, checkIndex, checkIndices, checkVectorDimensions, checkVectorDimensions, combine, combineToSelf, cosine, dotProduct, getL1Norm, getLInfNorm, getMaxIndex, getMaxValue, getMinIndex, getMinValue, getNorm, iterator, map, mapDivide, mapDivideToSelf, mapMultiply, mapMultiplyToSelf, mapSubtract, mapSubtractToSelf, mapToSelf, outerProduct, projection, unmodifiableRealVector, walkInDefaultOrder, walkInDefaultOrder, walkInDefaultOrder, walkInDefaultOrder, walkInOptimizedOrder, walkInOptimizedOrder, walkInOptimizedOrder, walkInOptimizedOrder
-
Field Details
-
DEFAULT_ZERO_TOLERANCE
public static final double DEFAULT_ZERO_TOLERANCEDefault Tolerance for having a value considered zero.- See Also:
-
-
Constructor Details
-
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 theOpenMapRealVector(OpenMapRealVector, int)
constructor or one of theappend
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
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
Create from an array. Only non-zero entries will be stored.- Parameters:
values
- The set of values to create from
-
OpenMapRealVector
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
Copy constructor.- Parameters:
v
- Instance to copy from.
-
OpenMapRealVector
Generic copy constructor.- Parameters:
v
- Instance to copy from.
-
-
Method Details
-
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.
-
add
Compute the sum of this vector andv
. Returns a new vector. Does not change instance data.- Overrides:
add
in classRealVector
- Parameters:
v
- Vector to be added.- Returns:
this
+v
.- Throws:
MathIllegalArgumentException
- ifv
is not the same size asthis
vector.
-
add
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
andv
. - Throws:
MathIllegalArgumentException
- if the dimensions do not match.
-
append
Optimized method to append a OpenMapRealVector.- Parameters:
v
- vector to append- Returns:
- The result of appending
v
to self
-
append
Construct a new vector by appending a vector to this vector.- Specified by:
append
in classRealVector
- Parameters:
v
- vector to append to this one.- Returns:
- a new vector.
-
append
Construct a new vector by appending a double to this vector.- Specified by:
append
in classRealVector
- Parameters:
d
- double to append.- Returns:
- a new vector.
-
copy
Returns a (deep) copy of this vector.- Specified by:
copy
in classRealVector
- Returns:
- a vector copy.
-
ebeDivide
Element-by-element division.- Specified by:
ebeDivide
in classRealVector
- Parameters:
v
- Vector by which instance elements must be divided.- Returns:
- a vector containing this[i] / v[i] for all i.
- Throws:
MathIllegalArgumentException
- ifv
is not the same size asthis
vector.
-
ebeMultiply
Element-by-element multiplication.- Specified by:
ebeMultiply
in classRealVector
- Parameters:
v
- Vector by which instance elements must be multiplied- Returns:
- a vector containing this[i] * v[i] for all i.
- Throws:
MathIllegalArgumentException
- ifv
is not the same size asthis
vector.
-
getSubVector
Get a subvector from consecutive elements.- Specified by:
getSubVector
in classRealVector
- Parameters:
index
- index of first element.n
- number of elements to be retrieved.- Returns:
- a vector containing n elements.
- Throws:
MathIllegalArgumentException
- if the index is not valid.
-
getDimension
public int getDimension()Returns the size of the vector.- Specified by:
getDimension
in classRealVector
- Returns:
- the size of this vector.
-
getDistance
Optimized method to compute distance.- Parameters:
v
- Vector to compute distance to.- Returns:
- the distance from
this
andv
. - Throws:
MathIllegalArgumentException
- if the dimensions do not match.
-
getDistance
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 Euclidean distance.
- Overrides:
getDistance
in classRealVector
- Parameters:
v
- Vector to which distance is requested.- Returns:
- the distance between two vectors.
- Throws:
MathIllegalArgumentException
- ifv
is not the same size asthis
vector.- See Also:
-
getEntry
Return the entry at the specified index.- Specified by:
getEntry
in classRealVector
- Parameters:
index
- Index location of entry to be fetched.- Returns:
- the vector entry at
index
. - Throws:
MathIllegalArgumentException
- if the index is not valid.- See Also:
-
getL1Distance
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
. - Throws:
MathIllegalArgumentException
- if the dimensions do not match.
-
getL1Distance
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 classRealVector
- Parameters:
v
- Vector to which distance is requested.- Returns:
- the distance between two vectors.
- Throws:
MathIllegalArgumentException
- ifv
is not the same size asthis
vector.
-
getLInfDistance
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 classRealVector
- Parameters:
v
- Vector to which distance is requested.- Returns:
- the distance between two vectors.
- Throws:
MathIllegalArgumentException
- ifv
is not the same size asthis
vector.- See Also:
-
isInfinite
public boolean isInfinite()Check whether any coordinate of this vector is infinite and none areNaN
.- Specified by:
isInfinite
in classRealVector
- Returns:
true
if any coordinate of this vector is infinite and none areNaN
,false
otherwise.
-
isNaN
public boolean isNaN()Check whether any coordinate of this vector isNaN
.- Specified by:
isNaN
in classRealVector
- Returns:
true
if any coordinate of this vector isNaN
,false
otherwise.
-
mapAdd
Add a value to each entry. Returns a new vector. Does not change instance data.- Overrides:
mapAdd
in classRealVector
- Parameters:
d
- Value to be added to each entry.- Returns:
this
+d
.
-
mapAddToSelf
Add a value to each entry. The instance is changed in-place.- Overrides:
mapAddToSelf
in classRealVector
- Parameters:
d
- Value to be added to each entry.- Returns:
this
.
-
setEntry
Set a single element.- Specified by:
setEntry
in classRealVector
- Parameters:
index
- element index.value
- new value for the element.- Throws:
MathIllegalArgumentException
- if the index is not valid.- See Also:
-
setSubVector
Set a sequence of consecutive elements.- Specified by:
setSubVector
in classRealVector
- Parameters:
index
- index of first element to be set.v
- vector containing the values to set.- Throws:
MathIllegalArgumentException
- if the index is not valid.
-
set
public void set(double value) Set all elements to a single value.- Overrides:
set
in classRealVector
- Parameters:
value
- Single value to set for all elements.
-
subtract
Optimized method to subtract OpenMapRealVectors.- Parameters:
v
- Vector to subtract fromthis
.- Returns:
- the difference of
this
andv
. - Throws:
MathIllegalArgumentException
- if the dimensions do not match.
-
subtract
Subtractv
from this vector. Returns a new vector. Does not change instance data.- Overrides:
subtract
in classRealVector
- Parameters:
v
- Vector to be subtracted.- Returns:
this
-v
.- Throws:
MathIllegalArgumentException
- ifv
is not the same size asthis
vector.
-
unitVector
Creates a unit vector pointing in the direction of this vector. The instance is not changed by this method.- Overrides:
unitVector
in classRealVector
- Returns:
- a unit vector pointing in direction of this vector.
- Throws:
MathRuntimeException
- if the norm is zero.
-
unitize
Converts this vector into a unit vector. The instance itself is changed by this method.- Overrides:
unitize
in classRealVector
- Throws:
MathRuntimeException
- if the norm is zero.
-
toArray
public double[] toArray()Convert the vector to an array ofdouble
s. The array is independent from this vector data: the elements are copied.- Overrides:
toArray
in classRealVector
- Returns:
- an array containing a copy of the vector elements.
-
hashCode
public int hashCode(). This method must be overriden by concrete subclasses ofRealVector
(current implementation throws an exception). Implementation Note: This works on exact values, and as a result it is possible fora.subtract(b)
to be the zero vector, whilea.hashCode() != b.hashCode()
.- Overrides:
hashCode
in classRealVector
-
equals
Test for the equality of two real vectors. If all coordinates of two real vectors are exactly the same, and none are
NaN
, the two real vectors are considered to be equal.NaN
coordinates are considered to affect globally the vector and be equals to each other - i.e, if either (or all) coordinates of the real vector are equal toNaN
, the real vector is equal to a vector with allNaN
coordinates.This method must be overriden by concrete subclasses of
Implementation Note: This performs an exact comparison, and as a result it is possible forRealVector
(the current implementation throws an exception).a.subtract(b
} to be the zero vector, whilea.equals(b) == false
.- Overrides:
equals
in classRealVector
- Parameters:
obj
- Object to test for equality.- Returns:
true
if two vector objects are equal,false
ifother
is null, not an instance ofRealVector
, or not equal to thisRealVector
instance.
-
getSparsity
public double getSparsity()Get percentage of none zero elements as a decimal percent.- Returns:
- the percentage of none zero elements as a decimal percent
-
sparseIterator
Create a sparse iterator over the vector, which may omit some entries. The ommitted entries are either exact zeroes (for dense implementations) or are the entries which are not stored (for real sparse vectors). No guarantees are made about order of iteration.Note: derived classes are required to return an
Iterator
that returns non-nullRealVector.Entry
objects as long asIterator.hasNext()
returnstrue
.- Overrides:
sparseIterator
in classRealVector
- Returns:
- a sparse iterator.
-