Package weka.core.neighboursearch
Class LinearNNSearch
- java.lang.Object
-
- weka.core.neighboursearch.NearestNeighbourSearch
-
- weka.core.neighboursearch.LinearNNSearch
-
- All Implemented Interfaces:
java.io.Serializable
,AdditionalMeasureProducer
,OptionHandler
,RevisionHandler
public class LinearNNSearch extends NearestNeighbourSearch
Class implementing the brute force search algorithm for nearest neighbour search. Valid options are:-S Skip identical instances (distances equal to zero).
- Version:
- $Revision: 1.2 $
- Author:
- Ashraf M. Kibriya (amk14[at-the-rate]cs[dot]waikato[dot]ac[dot]nz)
- See Also:
- Serialized Form
-
-
Constructor Summary
Constructors Constructor Description LinearNNSearch()
Constructor.LinearNNSearch(Instances insts)
Constructor that uses the supplied set of instances.
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
addInstanceInfo(Instance ins)
Adds the given instance info.double[]
getDistances()
Returns the distances of the k nearest neighbours.java.lang.String[]
getOptions()
Gets the current settings.java.lang.String
getRevision()
Returns the revision string.boolean
getSkipIdentical()
Gets whether if identical instances are skipped from the neighbourhood.java.lang.String
globalInfo()
Returns a string describing this nearest neighbour search algorithm.Instances
kNearestNeighbours(Instance target, int kNN)
Returns k nearest instances in the current neighbourhood to the supplied instance.java.util.Enumeration
listOptions()
Returns an enumeration describing the available options.Instance
nearestNeighbour(Instance target)
Returns the nearest instance in the current neighbourhood to the supplied instance.void
setInstances(Instances insts)
Sets the instances comprising the current neighbourhood.void
setOptions(java.lang.String[] options)
Parses a given list of options.void
setSkipIdentical(boolean skip)
Sets the property to skip identical instances (with distance zero from the target) from the set of neighbours returned.java.lang.String
skipIdenticalTipText()
Returns the tip text for this property.void
update(Instance ins)
Updates the LinearNNSearch to cater for the new added instance.-
Methods inherited from class weka.core.neighboursearch.NearestNeighbourSearch
combSort11, distanceFunctionTipText, enumerateMeasures, getDistanceFunction, getInstances, getMeasure, getMeasurePerformance, getPerformanceStats, measurePerformanceTipText, quickSort, setDistanceFunction, setMeasurePerformance
-
-
-
-
Constructor Detail
-
LinearNNSearch
public LinearNNSearch()
Constructor. Needs setInstances(Instances) to be called before the class is usable.
-
LinearNNSearch
public LinearNNSearch(Instances insts)
Constructor that uses the supplied set of instances.- Parameters:
insts
- the instances to use
-
-
Method Detail
-
globalInfo
public java.lang.String globalInfo()
Returns a string describing this nearest neighbour search algorithm.- Overrides:
globalInfo
in classNearestNeighbourSearch
- Returns:
- a description of the algorithm for displaying in the explorer/experimenter gui
-
listOptions
public java.util.Enumeration listOptions()
Returns an enumeration describing the available options.- Specified by:
listOptions
in interfaceOptionHandler
- Overrides:
listOptions
in classNearestNeighbourSearch
- Returns:
- an enumeration of all the available options.
-
setOptions
public void setOptions(java.lang.String[] options) throws java.lang.Exception
Parses a given list of options. Valid options are:-S Skip identical instances (distances equal to zero).
- Specified by:
setOptions
in interfaceOptionHandler
- Overrides:
setOptions
in classNearestNeighbourSearch
- Parameters:
options
- the list of options as an array of strings- Throws:
java.lang.Exception
- if an option is not supported
-
getOptions
public java.lang.String[] getOptions()
Gets the current settings.- Specified by:
getOptions
in interfaceOptionHandler
- Overrides:
getOptions
in classNearestNeighbourSearch
- Returns:
- an array of strings suitable for passing to setOptions()
-
skipIdenticalTipText
public java.lang.String skipIdenticalTipText()
Returns the tip text for this property.- Returns:
- tip text for this property suitable for displaying in the explorer/experimenter gui
-
setSkipIdentical
public void setSkipIdentical(boolean skip)
Sets the property to skip identical instances (with distance zero from the target) from the set of neighbours returned.- Parameters:
skip
- if true, identical intances are skipped
-
getSkipIdentical
public boolean getSkipIdentical()
Gets whether if identical instances are skipped from the neighbourhood.- Returns:
- true if identical instances are skipped
-
nearestNeighbour
public Instance nearestNeighbour(Instance target) throws java.lang.Exception
Returns the nearest instance in the current neighbourhood to the supplied instance.- Specified by:
nearestNeighbour
in classNearestNeighbourSearch
- Parameters:
target
- The instance to find the nearest neighbour for.- Returns:
- the nearest instance
- Throws:
java.lang.Exception
- if the nearest neighbour could not be found.
-
kNearestNeighbours
public Instances kNearestNeighbours(Instance target, int kNN) throws java.lang.Exception
Returns k nearest instances in the current neighbourhood to the supplied instance.- Specified by:
kNearestNeighbours
in classNearestNeighbourSearch
- Parameters:
target
- The instance to find the k nearest neighbours for.kNN
- The number of nearest neighbours to find.- Returns:
- the k nearest neighbors
- Throws:
java.lang.Exception
- if the neighbours could not be found.
-
getDistances
public double[] getDistances() throws java.lang.Exception
Returns the distances of the k nearest neighbours. The kNearestNeighbours or nearestNeighbour must always be called before calling this function. If this function is called before calling either the kNearestNeighbours or the nearestNeighbour, then it throws an exception. If, however, if either of the nearestNeighbour functions are called at any point in the past then no exception is thrown and the distances of the training set from the last supplied target instance (to either one of the nearestNeighbour functions) is/are returned.- Specified by:
getDistances
in classNearestNeighbourSearch
- Returns:
- array containing the distances of the nearestNeighbours. The length and ordering of the array is the same as that of the instances returned by nearestNeighbour functions.
- Throws:
java.lang.Exception
- if called before calling kNearestNeighbours or nearestNeighbours.
-
setInstances
public void setInstances(Instances insts) throws java.lang.Exception
Sets the instances comprising the current neighbourhood.- Overrides:
setInstances
in classNearestNeighbourSearch
- Parameters:
insts
- The set of instances on which the nearest neighbour search is carried out. Usually this set is the training set.- Throws:
java.lang.Exception
- if setting of instances fails
-
update
public void update(Instance ins) throws java.lang.Exception
Updates the LinearNNSearch to cater for the new added instance. This implementation only updates the ranges of the DistanceFunction class, since our set of instances is passed by reference and should already have the newly added instance.- Specified by:
update
in classNearestNeighbourSearch
- Parameters:
ins
- The instance to add. Usually this is the instance that is added to our neighbourhood i.e. the training instances.- Throws:
java.lang.Exception
- if the given instances are null
-
addInstanceInfo
public void addInstanceInfo(Instance ins)
Adds the given instance info. This implementation updates the range datastructures of the DistanceFunction class.- Overrides:
addInstanceInfo
in classNearestNeighbourSearch
- Parameters:
ins
- The instance to add the information of. Usually this is the test instance supplied to update the range of attributes in the distance function.
-
getRevision
public java.lang.String getRevision()
Returns the revision string.- Returns:
- the revision
-
-