SHOGUN  4.1.0
CZeroMeanCenterKernelNormalizer Class Reference

## Detailed Description

ZeroMeanCenterKernelNormalizer centers the kernel in feature space.

After centering, each feature must have zero mean. The centered kernel matrix can be expressed in terms of the non-centered version.

Denoting the mapping from input space to feature space by $$\phi:\mathcal{X}\rightarrow\mathcal{F}$$, the centered square kernel matrix $$K_c$$ (with dimensionality $$M$$)

can be expressed in terms of the original matrix $$K$$ as follows:

\begin{eqnarray*} k({\bf x}_i,{\bf x}_j)_c & = & \left(\phi({\bf x}_i) - \frac{1}{m} \sum_{p=1}^M \phi({\bf x}_p)\right) \cdot \left(\phi({\bf x}_j) - \frac{1}{M} \sum_{q=1}^M \phi({\bf x}_q)\right) \\ & = & K_{ij} - \frac{1}{M} \sum_{p=1}^M K_{pj} - \frac{1}{M} \sum_{q=1}^M K_{iq} + \frac{1}{M^2} \sum_{p=1}^M \sum_{q=1}^M K_{pq} \\ & = & (K - 1_M K - K 1_M + 1_M K 1_M)_{ij} \end{eqnarray*}

Additionally, let $$K^{t}$$ be the $$L \times M$$ test matrix describing the similarity between a $$L$$ test instances with $$M$$ training instances

(defined by a $$M x M$$ kernel matrix $$K$$), the centered testing set kernel matrix is given by

$K_{c}^t = (K - 1'_M K - K^{t} 1_M + 1'_M K 1_M)$

Definition at line 43 of file ZeroMeanCenterKernelNormalizer.h.

Inheritance diagram for CZeroMeanCenterKernelNormalizer:
[legend]

## Public Member Functions

CZeroMeanCenterKernelNormalizer ()

virtual ~CZeroMeanCenterKernelNormalizer ()

virtual bool init (CKernel *k)

virtual float64_t normalize (float64_t value, int32_t idx_lhs, int32_t idx_rhs)

virtual float64_t normalize_lhs (float64_t value, int32_t idx_lhs)

virtual float64_t normalize_rhs (float64_t value, int32_t idx_rhs)

bool alloc_and_compute_row_means (CKernel *k, float64_t *&v, int32_t num_lhs, int32_t num_rhs)

virtual const char * get_name () const

virtual void register_params ()

ENormalizerType get_normalizer_type ()

void set_normalizer_type (ENormalizerType type)

virtual CSGObjectshallow_copy () const

virtual CSGObjectdeep_copy () const

virtual bool is_generic (EPrimitiveType *generic) const

template<class T >
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

template<>
void set_generic ()

void unset_generic ()

virtual void print_serializable (const char *prefix="")

virtual bool save_serializable (CSerializableFile *file, const char *prefix="")

virtual bool load_serializable (CSerializableFile *file, const char *prefix="")

void set_global_io (SGIO *io)

SGIOget_global_io ()

void set_global_parallel (Parallel *parallel)

Parallelget_global_parallel ()

void set_global_version (Version *version)

Versionget_global_version ()

SGStringList< char > get_modelsel_names ()

void print_modsel_params ()

char * get_modsel_param_descr (const char *param_name)

index_t get_modsel_param_index (const char *param_name)

void build_gradient_parameter_dictionary (CMap< TParameter *, CSGObject * > *dict)

virtual void update_parameter_hash ()

virtual bool parameter_hash_changed ()

virtual bool equals (CSGObject *other, float64_t accuracy=0.0, bool tolerant=false)

virtual CSGObjectclone ()

## Public Attributes

SGIOio

Parallelparallel

Versionversion

Parameterm_parameters

Parameterm_model_selection_parameters

uint32_t m_hash

## Protected Member Functions

virtual void load_serializable_pre () throw (ShogunException)

virtual void load_serializable_post () throw (ShogunException)

virtual void save_serializable_pre () throw (ShogunException)

virtual void save_serializable_post () throw (ShogunException)

## Protected Attributes

float64_tktrain_row_means

int32_t num_ktrain

float64_tktest_row_means

int32_t num_ktest

float64_t ktrain_mean

ENormalizerType m_type

## Constructor & Destructor Documentation

 CZeroMeanCenterKernelNormalizer ( )

default constructor

Definition at line 48 of file ZeroMeanCenterKernelNormalizer.h.

 virtual ~CZeroMeanCenterKernelNormalizer ( )
virtual

default destructor

Definition at line 59 of file ZeroMeanCenterKernelNormalizer.h.

## Member Function Documentation

 bool alloc_and_compute_row_means ( CKernel * k, float64_t *& v, int32_t num_lhs, int32_t num_rhs )

alloc and compute the vector containing the row margins of all rows for a kernel matrix.

Definition at line 137 of file ZeroMeanCenterKernelNormalizer.h.

 void build_gradient_parameter_dictionary ( CMap< TParameter *, CSGObject * > * dict )
inherited

Builds a dictionary of all parameters in SGObject as well of those of SGObjects that are parameters of this object. Dictionary maps parameters to the objects that own them.

Parameters
 dict dictionary of parameters to be built.

Definition at line 597 of file SGObject.cpp.

 CSGObject * clone ( )
virtualinherited

Creates a clone of the current object. This is done via recursively traversing all parameters, which corresponds to a deep copy. Calling equals on the cloned object always returns true although none of the memory of both objects overlaps.

Returns
an identical copy of the given object, which is disjoint in memory. NULL if the clone fails. Note that the returned object is SG_REF'ed

Definition at line 714 of file SGObject.cpp.

 CSGObject * deep_copy ( ) const
virtualinherited

A deep copy. All the instance variables will also be copied.

Definition at line 198 of file SGObject.cpp.

 bool equals ( CSGObject * other, float64_t accuracy = 0.0, bool tolerant = false )
virtualinherited

Recursively compares the current SGObject to another one. Compares all registered numerical parameters, recursion upon complex (SGObject) parameters. Does not compare pointers!

May be overwritten but please do with care! Should not be necessary in most cases.

Parameters
 other object to compare with accuracy accuracy to use for comparison (optional) tolerant allows linient check on float equality (within accuracy)
Returns
true if all parameters were equal, false if not

Definition at line 618 of file SGObject.cpp.

 SGIO * get_global_io ( )
inherited

get the io object

Returns
io object

Definition at line 235 of file SGObject.cpp.

 Parallel * get_global_parallel ( )
inherited

get the parallel object

Returns
parallel object

Definition at line 277 of file SGObject.cpp.

 Version * get_global_version ( )
inherited

get the version object

Returns
version object

Definition at line 290 of file SGObject.cpp.

 SGStringList< char > get_modelsel_names ( )
inherited
Returns
vector of names of all parameters which are registered for model selection

Definition at line 498 of file SGObject.cpp.

 char * get_modsel_param_descr ( const char * param_name )
inherited

Returns description of a given parameter string, if it exists. SG_ERROR otherwise

Parameters
 param_name name of the parameter
Returns
description of the parameter

Definition at line 522 of file SGObject.cpp.

 index_t get_modsel_param_index ( const char * param_name )
inherited

Returns index of model selection parameter with provided index

Parameters
 param_name name of model selection parameter
Returns
index of model selection parameter with provided name, -1 if there is no such

Definition at line 535 of file SGObject.cpp.

 virtual const char* get_name ( ) const
virtual
Returns
object name

Implements CSGObject.

Definition at line 152 of file ZeroMeanCenterKernelNormalizer.h.

 ENormalizerType get_normalizer_type ( )
inherited

getter for normalizer type

Definition at line 102 of file KernelNormalizer.h.

 virtual bool init ( CKernel * k )
virtual

initialization of the normalizer

Parameters
 k kernel

Implements CKernelNormalizer.

Definition at line 67 of file ZeroMeanCenterKernelNormalizer.h.

 bool is_generic ( EPrimitiveType * generic ) const
virtualinherited

If the SGSerializable is a class template then TRUE will be returned and GENERIC is set to the type of the generic.

Parameters
 generic set to the type of the generic if returning TRUE
Returns
TRUE if a class template.

Definition at line 296 of file SGObject.cpp.

 bool load_serializable ( CSerializableFile * file, const char * prefix = "" )
virtualinherited

Load this object from file. If it will fail (returning FALSE) then this object will contain inconsistent data and should not be used!

Parameters
 file where to load from prefix prefix for members
Returns
TRUE if done, otherwise FALSE

Definition at line 369 of file SGObject.cpp.

 void load_serializable_post ( ) throw ( ShogunException )
protectedvirtualinherited

Can (optionally) be overridden to post-initialize some member variables which are not PARAMETER::ADD'ed. Make sure that at first the overridden method BASE_CLASS::LOAD_SERIALIZABLE_POST is called.

Exceptions
 ShogunException will be thrown if an error occurs.

Definition at line 426 of file SGObject.cpp.

 void load_serializable_pre ( ) throw ( ShogunException )
protectedvirtualinherited

Can (optionally) be overridden to pre-initialize some member variables which are not PARAMETER::ADD'ed. Make sure that at first the overridden method BASE_CLASS::LOAD_SERIALIZABLE_PRE is called.

Exceptions
 ShogunException will be thrown if an error occurs.

Definition at line 421 of file SGObject.cpp.

 virtual float64_t normalize ( float64_t value, int32_t idx_lhs, int32_t idx_rhs )
virtual

normalize the kernel value

Parameters
 value kernel value idx_lhs index of left hand side vector idx_rhs index of right hand side vector

Implements CKernelNormalizer.

Definition at line 106 of file ZeroMeanCenterKernelNormalizer.h.

 virtual float64_t normalize_lhs ( float64_t value, int32_t idx_lhs )
virtual

normalize only the left hand side vector

Parameters
 value value of a component of the left hand side feature vector idx_lhs index of left hand side vector

Implements CKernelNormalizer.

Definition at line 117 of file ZeroMeanCenterKernelNormalizer.h.

 virtual float64_t normalize_rhs ( float64_t value, int32_t idx_rhs )
virtual

normalize only the right hand side vector

Parameters
 value value of a component of the right hand side feature vector idx_rhs index of right hand side vector

Implements CKernelNormalizer.

Definition at line 127 of file ZeroMeanCenterKernelNormalizer.h.

 bool parameter_hash_changed ( )
virtualinherited
Returns
whether parameter combination has changed since last update

Definition at line 262 of file SGObject.cpp.

 void print_modsel_params ( )
inherited

prints all parameter registered for model selection and their type

Definition at line 474 of file SGObject.cpp.

 void print_serializable ( const char * prefix = "" )
virtualinherited

prints registered parameters out

Parameters
 prefix prefix for members

Definition at line 308 of file SGObject.cpp.

 virtual void register_params ( )
virtualinherited

register the parameters

Definition at line 94 of file KernelNormalizer.h.

 bool save_serializable ( CSerializableFile * file, const char * prefix = "" )
virtualinherited

Save this object to file.

Parameters
 file where to save the object; will be closed during returning if PREFIX is an empty string. prefix prefix for members
Returns
TRUE if done, otherwise FALSE

Definition at line 314 of file SGObject.cpp.

 void save_serializable_post ( ) throw ( ShogunException )
protectedvirtualinherited

Can (optionally) be overridden to post-initialize some member variables which are not PARAMETER::ADD'ed. Make sure that at first the overridden method BASE_CLASS::SAVE_SERIALIZABLE_POST is called.

Exceptions
 ShogunException will be thrown if an error occurs.

Reimplemented in CKernel.

Definition at line 436 of file SGObject.cpp.

 void save_serializable_pre ( ) throw ( ShogunException )
protectedvirtualinherited

Can (optionally) be overridden to pre-initialize some member variables which are not PARAMETER::ADD'ed. Make sure that at first the overridden method BASE_CLASS::SAVE_SERIALIZABLE_PRE is called.

Exceptions
 ShogunException will be thrown if an error occurs.

Definition at line 431 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 41 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 46 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 51 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 56 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 61 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 66 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 71 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 76 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 81 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 86 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 91 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 96 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 101 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 106 of file SGObject.cpp.

 void set_generic ( )
inherited

Definition at line 111 of file SGObject.cpp.

 void set_generic ( )
inherited

set generic type to T

 void set_global_io ( SGIO * io )
inherited

set the io object

Parameters
 io io object to use

Definition at line 228 of file SGObject.cpp.

 void set_global_parallel ( Parallel * parallel )
inherited

set the parallel object

Parameters
 parallel parallel object to use

Definition at line 241 of file SGObject.cpp.

 void set_global_version ( Version * version )
inherited

set the version object

Parameters
 version version object to use

Definition at line 283 of file SGObject.cpp.

 void set_normalizer_type ( ENormalizerType type )
inherited

setter for normalizer type

Parameters
 type type of normalizer

Definition at line 110 of file KernelNormalizer.h.

 CSGObject * shallow_copy ( ) const
virtualinherited

A shallow copy. All the SGObject instance variables will be simply assigned and SG_REF-ed.

Reimplemented in CGaussianKernel.

Definition at line 192 of file SGObject.cpp.

 void unset_generic ( )
inherited

unset generic type

this has to be called in classes specializing a template class

Definition at line 303 of file SGObject.cpp.

 void update_parameter_hash ( )
virtualinherited

Updates the hash of current parameter combination

Definition at line 248 of file SGObject.cpp.

## Member Data Documentation

 SGIO* io
inherited

io

Definition at line 369 of file SGObject.h.

 float64_t* ktest_row_means
protected

test row means

Definition at line 162 of file ZeroMeanCenterKernelNormalizer.h.

 float64_t ktrain_mean
protected

train mean

Definition at line 168 of file ZeroMeanCenterKernelNormalizer.h.

 float64_t* ktrain_row_means
protected

train row means

Definition at line 156 of file ZeroMeanCenterKernelNormalizer.h.

inherited

parameters wrt which we can compute gradients

Definition at line 384 of file SGObject.h.

 uint32_t m_hash
inherited

Hash of parameter values

Definition at line 387 of file SGObject.h.

 Parameter* m_model_selection_parameters
inherited

model selection parameters

Definition at line 381 of file SGObject.h.

 Parameter* m_parameters
inherited

parameters

Definition at line 378 of file SGObject.h.

 ENormalizerType m_type
protectedinherited

normalizer type

Definition at line 117 of file KernelNormalizer.h.

 int32_t num_ktest
protected

num k test

Definition at line 165 of file ZeroMeanCenterKernelNormalizer.h.

 int32_t num_ktrain
protected

num k train

Definition at line 159 of file ZeroMeanCenterKernelNormalizer.h.

 Parallel* parallel
inherited

parallel

Definition at line 372 of file SGObject.h.

 Version* version
inherited

version

Definition at line 375 of file SGObject.h.

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

SHOGUN Machine Learning Toolbox - Documentation