Different Loaders. More...

#include <mknn_dataset_loader.hpp>

Static Public Member Functions
static Dataset	Custom (DatasetCustom *custom_dataset, bool delete_custom_dataset_on_dataset_release, Domain domain)
	Creates a new custom dataset. More...

static Dataset	PointerArray (void **object_array, long long num_objects, Domain domain)
	Creates a new dataset from an array of objects. More...

static Dataset	PointerCompactVectors (void *vectors_header, long long num_vectors, long long vector_num_dimensions, const std::string vector_dimension_datatype)
	Creates a new dataset from a data array. More...

static Dataset	ParseVectorFile (std::string filename, const std::string datatype)
	Creates a new dataset by reading a text file with vectors. More...

static Dataset	ParseStringsFile (std::string filename)
	Creates a new dataset by reading a text file with strings. More...

static DatasetConcatenate	Concatenate (const std::vector< Dataset > &subdatasets)
	Creates a new dataset which is the concatenation of one or more datasets. More...

static Dataset	SubsetSegment (Dataset &superdataset, long long position_start, long long length)
	Creates a new dataset which is a subset of a bigger dataset. More...

static Dataset	SubsetPositions (Dataset &superdataset, long long *positions, long long num_positions)
	Creates a new dataset which is a subset of a bigger dataset. More...

static Dataset	UniformRandomVectors (long long num_objects, long long dimension, double dimension_minValueIncluded, double dimension_maxValueNotIncluded, const std::string datatype)
	Creates a new dataset with random vectors of the given datatype. More...

static DatasetMultiObject	MultiObject (const std::vector< Dataset > &subdatasets)
	Creates a new dataset where each object is a multi-object. More...

static Dataset	Empty (Domain domain)
	Creates a new empty dataset that can dynamically grow as new objects are added. More...

Detailed Description

Different Loaders.

Member Function Documentation

static DatasetConcatenate mknn::DatasetLoader::Concatenate ( const std::vector< Dataset > & subdatasets )

static

Creates a new dataset which is the concatenation of one or more datasets.

Parameters

subdatasets	the array of datasets
delete_subdatasets_on_dataset_release	all `subdatasets`[i] must be released (by calling delete) during delete of the new dataset.

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

static Dataset mknn::DatasetLoader::Custom	(	DatasetCustom *	custom_dataset,
		bool	delete_custom_dataset_on_dataset_release,
		Domain	domain
	)

static

Creates a new custom dataset.

The custom dataset must implement the DatasetCustom abstract class.

Parameters

custom_dataset	the object that stores and is used to obtain objects
delete_custom_dataset_on_dataset_release	binds the lifetime of `custom_dataset` to the new dataset object
domain	the domain for the objects returned by `custom_dataset`.
delete_domain_on_dataset_release	binds the lifetime of `domain` to this dataset.

Returns: a new dataset object

static Dataset mknn::DatasetLoader::Empty ( Domain domain )

static

Creates a new empty dataset that can dynamically grow as new objects are added.

The new objects are added by Dataset::pushObject.

Parameters

domain	the domain for the objects that will be added to this dataset.
delete_domain_on_dataset_release	binds the lifetime of `domain` to this dataset.

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

static DatasetMultiObject mknn::DatasetLoader::MultiObject ( const std::vector< Dataset > & subdatasets )

static

Creates a new dataset where each object is a multi-object.

Each multi-object is created by combining one object of each subdataset. All datasets must contain the same number of objects.

Parameters

subdatasets	the datasets from which multi-objects will be created.
delete_subdatasets_on_dataset_release	all `subdatasets`[i] must be released (by calling delete) during delete of the new dataset.

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

static Dataset mknn::DatasetLoader::ParseStringsFile ( std::string filename )

static

Creates a new dataset by reading a text file with strings.

The format is one string per line.

Parameters

filename the filename to read.

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

static Dataset mknn::DatasetLoader::ParseVectorFile	(	std::string	filename,
		const std::string	datatype
	)

static

Creates a new dataset by reading a text file with vectors.

The format is one vector per line, each dimension separated by tab.

Parameters

filename	the filename to read.
datatype	the datatype of the objects.

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

static Dataset mknn::DatasetLoader::PointerArray	(	void **	object_array,
		long long	num_objects,
		Domain	domain
	)

static

Creates a new dataset from an array of objects.

The objects are read from object_array in the following order:

first object: object_array[0]
second object: object_array[1]
...
last object: object_array[num_objects - 1]

Parameters

object_array	pointer to an array of objects.
num_objects	number of object to read from the array.
domain	the domain for the objects in the array.
delete_domain_on_dataset_release	binds the lifetime of `domain` to this dataset.

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

static Dataset mknn::DatasetLoader::PointerCompactVectors	(	void *	vectors_header,
		long long	num_vectors,
		long long	vector_num_dimensions,
		const std::string	vector_dimension_datatype
	)

static

Creates a new dataset from a data array.

The objects are read from vectors_header in the following order:

first object: vectors_header
second object: vectors_header + vector_size
...
last object: vectors_header + (num_objects - 1) * vector_size.

The value of vector_size is determined by vector_num_dimensions and vector_dimension_datatype (see mknn::Domain::newVector and mknn::Domain::getVectorSizeInBytes).

Parameters

vectors_header	pointer to the header of the set of vectors.
num_vectors	number of object to read from `vectors_header`.
vector_num_dimensions	number of dimensions of the vectors.
vector_dimension_datatype	datatype for the vector values. See constants in mknn::Datatype.

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

static Dataset mknn::DatasetLoader::SubsetPositions	(	Dataset &	superdataset,
		long long *	positions,
		long long	num_positions
	)

static

Creates a new dataset which is a subset of a bigger dataset.

Parameters

superdataset	the dataset to extract objects
positions	each position of the objects to extract from `superdataset`. The positions are copied to an internal array.
num_positions	length of array `positions`. it must be greater than zero.

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

static Dataset mknn::DatasetLoader::SubsetSegment	(	Dataset &	superdataset,
		long long	position_start,
		long long	length
	)

static

Creates a new dataset which is a subset of a bigger dataset.

Parameters

superdataset	the dataset to extract objects
position_start	position of the first objects to extract.
length	number of consecutive objects to extract, starting from `position_start`. it must be greater than zero.

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

static Dataset mknn::DatasetLoader::UniformRandomVectors	(	long long	num_objects,
		long long	dimension,
		double	dimension_minValueIncluded,
		double	dimension_maxValueNotIncluded,
		const std::string	datatype
	)

static

Creates a new dataset with random vectors of the given datatype.

Each dimension is bounded in [0, dimension_max_value).

Parameters

num_objects	desired size of the dataset.
dimension	number of dimensions to generate.
dimension_minValueIncluded	the minimum value for each dimension (included).
dimension_maxValueNotIncluded	the maximum value for each dimension (not included).
datatype	the datatype of the generated vectors. See constants in mknn::Datatype.

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

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

src/metricknn/metricknn_cpp/mknn_dataset_loader.hpp

Static Public Member Functions

Detailed Description

Member Function Documentation