CLocalTangentSpaceAlignment Class Reference

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Detailed Description

the class LocalTangentSpaceAlignment used to preprocess data using Local Tangent Space Alignment (LTSA) algorithm as described in:

Zhang, Z., & Zha, H. (2002). Principal Manifolds and Nonlinear Dimension Reduction via Local Tangent Space Alignment. Journal of Shanghai University English Edition, 8(4), 406-424. SIAM. Retrieved from http://arxiv.org/abs/cs/0212008

The stated eigenproblem is solved in the same way as CLocallyLinearEmbedding (LAPACK or ARPACK if available).

The local tangent space alignment step is parallel. Neighborhood determination is parallel as in CLocallyLinearEmbedding.

This algorithm is pretty stable for variations of k parameter value but be sure it is set with a consistent value (at least 3-5) for reasonable results.

Definition at line 45 of file LocalTangentSpaceAlignment.h.

Inheritance diagram for CLocalTangentSpaceAlignment:

List of all members.

Public Member Functions
	CLocalTangentSpaceAlignment ()
virtual	~CLocalTangentSpaceAlignment ()
virtual bool	init (CFeatures *features)
virtual void	cleanup ()
virtual SGMatrix< float64_t >	apply_to_feature_matrix (CFeatures *features)
virtual SGVector< float64_t >	apply_to_feature_vector (SGVector< float64_t > vector)
virtual const char *	get_name () const
virtual EPreprocessorType	get_type () const
Static Protected Member Functions
static void *	run_ltsa_thread (void *p)

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Constructor & Destructor Documentation

CLocalTangentSpaceAlignment

(

)

constructor

Definition at line 68 of file LocalTangentSpaceAlignment.cpp.

~CLocalTangentSpaceAlignment

(

)

[virtual]

destructor

Definition at line 73 of file LocalTangentSpaceAlignment.cpp.

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Member Function Documentation

SGMatrix< float64_t > apply_to_feature_matrix

(

CFeatures *

features

)

[virtual]

apply preprocessor to feature matrix

Parameters:

features

Reimplemented from CLocallyLinearEmbedding.

Definition at line 86 of file LocalTangentSpaceAlignment.cpp.

SGVector< float64_t > apply_to_feature_vector

(

SGVector< float64_t >

vector

)

[virtual]

apply preprocessor to feature vector, not supported

Parameters:

vector

Reimplemented from CLocallyLinearEmbedding.

Definition at line 211 of file LocalTangentSpaceAlignment.cpp.

void cleanup

(

)

[virtual]

cleanup

Reimplemented from CLocallyLinearEmbedding.

Definition at line 82 of file LocalTangentSpaceAlignment.cpp.

virtual const char* get_name

(

void

)

const [virtual]

get name

Returns:

name of preprocessor

Reimplemented from CLocallyLinearEmbedding.

Definition at line 77 of file LocalTangentSpaceAlignment.h.

virtual EPreprocessorType get_type

(

)

const [virtual]

get type

Returns:

type of preprocessor

Reimplemented from CLocallyLinearEmbedding.

Definition at line 82 of file LocalTangentSpaceAlignment.h.

bool init

(

CFeatures *

features

)

[virtual]

init

Parameters:

features

Reimplemented from CLocallyLinearEmbedding.

Definition at line 77 of file LocalTangentSpaceAlignment.cpp.

void * run_ltsa_thread

(

void *

p

)

[static, protected]

run ltsa thread

Parameters:

p

thread params

Definition at line 217 of file LocalTangentSpaceAlignment.cpp.

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

• LocalTangentSpaceAlignment.h
• LocalTangentSpaceAlignment.cpp