A Index represents the index structure. More...

#include <mknn_index.hpp>

Public Member Functions
IndexParams &	getParameters ()
	Returns the parameters used to create or load the index. More...

Dataset &	getSearchDataset ()
	Returns the dataset used to create or load the index. More...

Distance &	getDistance ()
	Returns the distance used to create or load the index. More...

std::string	getIdPredefinedIndex ()
	returns the id of the predefined index. More...

void	save (std::string filename_write)
	Saves the built index to a file. More...

Resolver	newResolver (ResolverParams &parameters_resolver)
	Configures a new similarity search using the given index. More...

	Index ()
	Default constructor.

virtual	~Index ()
	Default destructor.

	Index (const Index &other)
	Copy constructor.

Index &	operator= (const Index &other)
	Assignment operator.

Static Public Member Functions
static Index	newPredefined (IndexParams &parameters, Dataset &search_dataset, Distance &distance)
	Instantiates a new index identified by the given parameters. More...

static Index	restore (std::string filename_read, Dataset &search_dataset, Distance &distance, IndexParams &more_parameters)
	Loads an index from a file. More...

Protected Attributes
std::unique_ptr< Impl >	pimpl
	opaque object

Detailed Description

A Index represents the index structure.

In order to create an index, at least two parameters must be provided:

a search Dataset, where the nearest neighbors will be searched in.
a Distance, the dissimilarity measure to be used to compare objects.

MetricKnn provides a set of pre-defined indexes identified by a unique distance identifier. Some valid IDs are:

LINEARSCAN The naive sequential scan of the search dataset.
LAESA The LAESA metric access method. http://dx.doi.org/10.1016/0167-8655(94)90095-7
FLANN-KDTREE The kd-tree, implemented by FLANN library.
FLANN-KMEANS The k-means tree, implemented by FLANN library.

The multidimensional indexes are implemented by the FLANN library. http://www.cs.ubc.ca/research/flann/

In order to simplify the creation of distances, there are defined constructors for the different distances which internally invoke Index::newPredefined.

Note: The complete list of pre-defined indexes provided by MetricKnn can be printed by calling PredefIndex::helpListIndexes. The parameters supported by each index can be printed by calling PredefIndex::helpPrintIndex.

Member Function Documentation

Distance& mknn::Index::getDistance ( )

Returns the distance used to create or load the index.

Returns: the distance used to create or load the index.

std::string mknn::Index::getIdPredefinedIndex ( )

returns the id of the predefined index.

Returns: the id of the predefined index.

IndexParams& mknn::Index::getParameters ( )

Returns the parameters used to create or load the index.

Returns: the parameters used to create or load the index.

Dataset& mknn::Index::getSearchDataset ( )

Returns the dataset used to create or load the index.

Returns: the dataset used to create or load the index.

static Index mknn::Index::newPredefined	(	IndexParams &	parameters,
		Dataset &	search_dataset,
		Distance &	distance
	)

static

Instantiates a new index identified by the given parameters.

Parameters

parameters	the definition of the index.
delete_parameters_on_index_release	binds the lifetime of `parameters` to the new index.
search_dataset	the data to be indexed. Any search on this index will return some object from `search_data`.
delete_search_dataset_on_index_release	binds the lifetime of `search_dataset` to the new index.
distance	a distance.
delete_distance_on_index_release	binds the lifetime of `distance` to the new index.

Returns: a index (must be released)

Resolver mknn::Index::newResolver ( ResolverParams & parameters_resolver )

Configures a new similarity search using the given index.

Parameters

parameters_resolver	parameters to be given to the index in order to resolve the search.
delete_parameters_on_resolver_release	binds the lifetime of `parameters_resolver` to the new resolver.

Returns: an object configured to resolve a similarity search.

static Index mknn::Index::restore	(	std::string	filename_read,
		Dataset &	search_dataset,
		Distance &	distance,
		IndexParams &	more_parameters
	)

static

Loads an index from a file.

The file must have been created by save.

Remarks: search_dataset and dist_factory must be the same that were used to create and save the index.

Parameters

filename_read	File to read. If the file does not exists an error is raised.
search_dataset	The search dataset that was used to build the index.
delete_search_dataset_on_index_release	binds the lifetime of `search_dataset` to the new index.
distance	The distance that was used to build the index.
delete_distance_on_index_release	binds the lifetime of `distance` to the new index.
more_parameters	any parameter that may override the stored parameters or new parameters that could not be saved.
delete_parameters_on_index_release	binds the lifetime of `more_parameters` to the new index.

Returns: a new index (it must be released with delete).

void mknn::Index::save ( std::string filename_write )

Saves the built index to a file.

It may create other files using filename_write as prefix. The created files may be in binary format for fast loading.

Remarks: The search_dataset is not saved and the distance factory are not saved.

Parameters

filename_write File to create. If the file already exists it is overwritten.

The documentation for this class was generated from the following file:

src/metricknn/metricknn_cpp/mknn_index.hpp

Public Member Functions

Static Public Member Functions

Protected Attributes

Detailed Description

Member Function Documentation