de.lmu.ifi.dbs.elki.database
Class SequentialDatabase<O extends DatabaseObject>

java.lang.Object
  de.lmu.ifi.dbs.elki.logging.AbstractLoggable
      de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable
          de.lmu.ifi.dbs.elki.database.AbstractDatabase<O>
              de.lmu.ifi.dbs.elki.database.SequentialDatabase<O>

Type Parameters:

O - the type of FeatureVector as element of the database

All Implemented Interfaces:

Database<O>, Result, Parameterizable, Iterable<Integer>

public class SequentialDatabase<O extends DatabaseObject>
extends AbstractDatabase<O>

SequentialDatabase is a simple implementation of a Database.

It does not support any index structure and holds all objects in main memory (as a Map).

Author:

Arthur Zimek

Field Summary

Fields inherited from class de.lmu.ifi.dbs.elki.database.AbstractDatabase

listenerList

Fields inherited from class de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable

optionHandler

Fields inherited from class de.lmu.ifi.dbs.elki.logging.AbstractLoggable

debug, logger

Constructor Summary

SequentialDatabase()
Provides a database for main memory holding all objects in a hashtable.

Method Summary

<D extends Distance<D>> List<List<DistanceResultPair<D>>>	bulkKNNQueryForID(List<Integer> ids, int k, DistanceFunction<O,D> distanceFunction) Retrieves the k nearest neighbors for the query objects.
<D extends Distance<D>> List<DistanceResultPair<D>>	kNNQueryForID(Integer id, int k, DistanceFunction<O,D> distanceFunction) Retrieves the k nearest neighbors for the query object.
<D extends Distance<D>> List<DistanceResultPair<D>>	kNNQueryForObject(O queryObject, int k, DistanceFunction<O,D> distanceFunction) Retrieves the k nearest neighbors for the query object.
<D extends Distance<D>> List<DistanceResultPair<D>>	rangeQuery(Integer id, String epsilon, DistanceFunction<O,D> distanceFunction) Performs a range query for the given object ID with the given epsilon range and the according distance function.
<D extends Distance<D>> List<DistanceResultPair<D>>	reverseKNNQuery(Integer id, int k, DistanceFunction<O,D> distanceFunction) Performs a reverse k-nearest neighbor query for the given object ID.
String	shortDescription() Provides a description for SequentialDatabase.

Methods inherited from class de.lmu.ifi.dbs.elki.database.AbstractDatabase

addDatabaseListener, associate, associateGlobally, delete, delete, deleteAssociations, dimensionality, fireObjectInserted, fireObjectRemoved, fireObjectsChanged, fireObjectsInserted, fireObjectsRemoved, get, getAssociation, getAssociations, getGlobalAssociation, getIDs, getObjects, insert, insert, isSet, isSetForAllObjects, isSetGlobally, iterator, partition, partition, randomSample, removeDatabaseListener, restoreID, setAssociations, setNewID, size

Methods inherited from class de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizable

addOption, addParameterizable, addParameterizable, checkGlobalParameterConstraints, collectOptions, getAttributeSettings, getParameters, rememberParametersExcept, removeOption, removeParameterizable, setParameters

Methods inherited from class de.lmu.ifi.dbs.elki.logging.AbstractLoggable

debugFine, debugFiner, debugFinest, exception, progress, verbose, warning

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface de.lmu.ifi.dbs.elki.utilities.optionhandling.Parameterizable

checkGlobalParameterConstraints, collectOptions, getParameters, setParameters

Constructor Detail

SequentialDatabase

public SequentialDatabase()

Provides a database for main memory holding all objects in a hashtable.

Method Detail

kNNQueryForObject

public <D extends Distance<D>> List<DistanceResultPair<D>> kNNQueryForObject(O queryObject,
                                                                             int k,
                                                                             DistanceFunction<O,D> distanceFunction)

Retrieves the k nearest neighbors for the query object. The result contains always exactly k objects, including the query object if it is an element of the database. Ties in case of equal distances are resolved by the underlying KNNList, see KNNList.add(DistanceResultPair).

Type Parameters:

D - distance type

Parameters:

queryObject - the query object

k - the number of nearest neighbors to be returned

distanceFunction - the distance function that computes the distances between the objects

Returns:

a List of the query results

See Also:

Database.kNNQueryForObject(DatabaseObject, int, DistanceFunction)

kNNQueryForID

public <D extends Distance<D>> List<DistanceResultPair<D>> kNNQueryForID(Integer id,
                                                                         int k,
                                                                         DistanceFunction<O,D> distanceFunction)

Retrieves the k nearest neighbors for the query object. The result contains always exactly k objects. Ties in case of equal distances are resolved by the underlying KNNList, see KNNList.add(DistanceResultPair).

Type Parameters:

D - distance type

Parameters:

id - the ID of the query object

k - the number of nearest neighbors to be returned

distanceFunction - the distance function that computes the distances between the objects

Returns:

a List of the query results

See Also:

Database.kNNQueryForObject(DatabaseObject, int, DistanceFunction)

bulkKNNQueryForID

public <D extends Distance<D>> List<List<DistanceResultPair<D>>> bulkKNNQueryForID(List<Integer> ids,
                                                                                   int k,
                                                                                   DistanceFunction<O,D> distanceFunction)

Retrieves the k nearest neighbors for the query objects. The result contains always exactly k objects. Ties in case of equal distances are resolved by the underlying KNNList, see KNNList.add(DistanceResultPair).

Type Parameters:

D - distance type

Parameters:

ids - the IDs of the query objects

k - the number of nearest neighbors to be returned

distanceFunction - the distance function that computes the distances between the objects

Returns:

a List of List of the query results

See Also:

Database.kNNQueryForObject(DatabaseObject, int, DistanceFunction)

rangeQuery

public <D extends Distance<D>> List<DistanceResultPair<D>> rangeQuery(Integer id,
                                                                      String epsilon,
                                                                      DistanceFunction<O,D> distanceFunction)

Description copied from interface: Database

Performs a range query for the given object ID with the given epsilon range and the according distance function.

The query result is sorted in ascending order w.r.t. the distance to the query object.

Type Parameters:

D - distance type

Parameters:

id - the ID of the query object

epsilon - the string representation of the query range

distanceFunction - the distance function that computes the distances between the objects

Returns:

a List of the query results

reverseKNNQuery

public <D extends Distance<D>> List<DistanceResultPair<D>> reverseKNNQuery(Integer id,
                                                                           int k,
                                                                           DistanceFunction<O,D> distanceFunction)

Description copied from interface: Database

Performs a reverse k-nearest neighbor query for the given object ID.

The query result is sorted in ascending order w.r.t. the distance to the query object.

Generally, it is assumed that the database does not contain less than k objects.

Type Parameters:

D - distance type

Parameters:

id - the ID of the query object

k - the size of k-nearest neighborhood of any database object o to contain a database object in order to include o in the result list

distanceFunction - the distance function that computes the distances between the objects

Returns:

a List of the query results

shortDescription

public String shortDescription()

Provides a description for SequentialDatabase.

Specified by:

shortDescription in interface Parameterizable

Overrides:

shortDescription in class AbstractParameterizable

Returns:

Description of the class