Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes

CCombinedKernel Class Reference

Detailed Description

The Combined kernel is used to combine a number of kernels into a single CombinedKernel object by linear combination.

It keeps pointers to the added sub-kernels $k_m({\bf x}, {\bf x'})$ and for each sub-kernel - a kernel specific weight $\beta_m$.

It is especially useful to combine kernels working on different domains and to combine kernels looking at independent features and requires CCombinedFeatures to be used.

It is defined as:

\[ k_{combined}({\bf x}, {\bf x'}) = \sum_{m=1}^M \beta_m k_m({\bf x}, {\bf x'}) \]

Definition at line 46 of file CombinedKernel.h.

Inheritance diagram for CCombinedKernel:
Inheritance graph
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List of all members.

Public Member Functions

 CCombinedKernel (int32_t size=10, bool append_subkernel_weights=false)
virtual ~CCombinedKernel ()
virtual bool init (CFeatures *lhs, CFeatures *rhs)
virtual void cleanup ()
virtual EKernelType get_kernel_type ()
virtual EFeatureType get_feature_type ()
virtual EFeatureClass get_feature_class ()
virtual const char * get_name () const
void list_kernels ()
CKernel * get_first_kernel ()
CKernel * get_first_kernel (CListElement *&current)
CKernel * get_kernel (int32_t idx)
CKernel * get_last_kernel ()
CKernel * get_next_kernel ()
CKernel * get_next_kernel (CListElement *&current)
bool insert_kernel (CKernel *k)
bool append_kernel (CKernel *k)
bool delete_kernel ()
bool get_append_subkernel_weights ()
int32_t get_num_subkernels ()
virtual bool has_features ()
virtual void remove_lhs ()
virtual void remove_rhs ()
virtual void remove_lhs_and_rhs ()
virtual bool init_optimization (int32_t count, int32_t *IDX, float64_t *weights)
virtual bool delete_optimization ()
virtual float64_t compute_optimized (int32_t idx)
virtual void compute_batch (int32_t num_vec, int32_t *vec_idx, float64_t *target, int32_t num_suppvec, int32_t *IDX, float64_t *alphas, float64_t factor=1.0)
void emulate_compute_batch (CKernel *k, int32_t num_vec, int32_t *vec_idx, float64_t *target, int32_t num_suppvec, int32_t *IDX, float64_t *weights)
virtual void add_to_normal (int32_t idx, float64_t weight)
virtual void clear_normal ()
virtual void compute_by_subkernel (int32_t idx, float64_t *subkernel_contrib)
virtual const float64_t * get_subkernel_weights (int32_t &num_weights)
virtual SGVector< float64_t > get_subkernel_weights ()
virtual void set_subkernel_weights (SGVector< float64_t > weights)
virtual void set_optimization_type (EOptimizationType t)
bool precompute_subkernels ()
CCombinedKernel * KernelToCombinedKernel (shogun::CKernel *n)

Static Public Member Functions

static void * compute_optimized_kernel_helper (void *p)
static void * compute_kernel_helper (void *p)

Protected Member Functions

virtual float64_t compute (int32_t x, int32_t y)
void adjust_num_lhs_rhs_initialized (CKernel *k)

Protected Attributes

CList * kernel_list
int32_t sv_count
int32_t * sv_idx
float64_t * sv_weight
float64_t * subkernel_weights_buffer
bool append_subkernel_weights
bool initialized

Constructor & Destructor Documentation

CCombinedKernel ( int32_t  size = 10,
bool  append_subkernel_weights = false 
)

constructor

Parameters:
size cache size
append_subkernel_weights if subkernel weights shall be appended

Definition at line 45 of file CombinedKernel.cpp.

~CCombinedKernel (  )  [virtual]

Definition at line 56 of file CombinedKernel.cpp.

Member Function Documentation

void add_to_normal ( int32_t  idx,
float64_t  weight 
) [virtual]

add to normal vector

Parameters:
idx where to add
weight what to add

Reimplemented from CKernel.

Definition at line 579 of file CombinedKernel.cpp.

void adjust_num_lhs_rhs_initialized ( CKernel *  k  )  [protected]

adjust the variables num_lhs, num_rhs and initialized based on the kernel to be appended/inserted

Parameters:
k kernel

Definition at line 399 of file CombinedKernel.h.

bool append_kernel ( CKernel *  k  ) 

append kernel

Parameters:
k kernel
Returns:
if appending was successful

Definition at line 190 of file CombinedKernel.h.

void cleanup (  )  [virtual]

clean up kernel

Reimplemented from CKernel.

Definition at line 205 of file CombinedKernel.cpp.

void clear_normal (  )  [virtual]

clear normal vector

Reimplemented from CKernel.

Definition at line 593 of file CombinedKernel.cpp.

float64_t compute ( int32_t  x,
int32_t  y 
) [protected, virtual]

compute kernel function

Parameters:
x x
y y
Returns:
computed kernel function

Implements CKernel.

Definition at line 243 of file CombinedKernel.cpp.

void compute_batch ( int32_t  num_vec,
int32_t *  vec_idx,
float64_t *  target,
int32_t  num_suppvec,
int32_t *  IDX,
float64_t *  alphas,
float64_t  factor = 1.0 
) [virtual]

computes output for a batch of examples in an optimized fashion (favorable if kernel supports it, i.e. has KP_BATCHEVALUATION. to the outputvector target (of length num_vec elements) the output for the examples enumerated in vec_idx are added. therefore make sure that it is initialized with ZERO. the following num_suppvec, IDX, alphas arguments are the number of support vectors, their indices and weights

Reimplemented from CKernel.

Definition at line 336 of file CombinedKernel.cpp.

void compute_by_subkernel ( int32_t  idx,
float64_t *  subkernel_contrib 
) [virtual]

compute by subkernel

Parameters:
idx index
subkernel_contrib subkernel contribution

Reimplemented from CKernel.

Definition at line 607 of file CombinedKernel.cpp.

void * compute_kernel_helper ( void *  p  )  [static]

helper for compute kernel

Parameters:
p thread parameter

Definition at line 383 of file CombinedKernel.cpp.

float64_t compute_optimized ( int32_t  idx  )  [virtual]

compute optimized

Parameters:
idx index to compute
Returns:
optimized value at given index

Reimplemented from CKernel.

Definition at line 534 of file CombinedKernel.cpp.

void * compute_optimized_kernel_helper ( void *  p  )  [static]

helper for compute optimized kernel

Parameters:
p thread parameter

Definition at line 370 of file CombinedKernel.cpp.

bool delete_kernel (  ) 

delete kernel

Returns:
if deleting was successful

Definition at line 206 of file CombinedKernel.h.

bool delete_optimization (  )  [virtual]

delete optimization

Returns:
if deleting was successful

Reimplemented from CKernel.

Definition at line 310 of file CombinedKernel.cpp.

void emulate_compute_batch ( CKernel *  k,
int32_t  num_vec,
int32_t *  vec_idx,
float64_t *  target,
int32_t  num_suppvec,
int32_t *  IDX,
float64_t *  weights 
)

emulates batch computation, via linadd optimization w^t x or even down to sum_i alpha_i K(x_i,x)

Parameters:
k kernel
num_vec number of vectors
vec_idx vector index
target target
num_suppvec number of support vectors
IDX IDX
weights weights

Definition at line 405 of file CombinedKernel.cpp.

bool get_append_subkernel_weights (  ) 

check if subkernel weights are appended

Returns:
if subkernel weigths are appended

Definition at line 224 of file CombinedKernel.h.

virtual EFeatureClass get_feature_class (  )  [virtual]

return feature class the kernel can deal with

Returns:
feature class COMBINED

Implements CKernel.

Definition at line 92 of file CombinedKernel.h.

virtual EFeatureType get_feature_type (  )  [virtual]

return feature type the kernel can deal with

Returns:
feature type UNKNOWN

Implements CKernel.

Definition at line 83 of file CombinedKernel.h.

CKernel* get_first_kernel (  ) 

get first kernel

Returns:
first kernel

Definition at line 110 of file CombinedKernel.h.

CKernel* get_first_kernel ( CListElement *&  current  ) 

get first kernel

Parameters:
current 
Returns:
first kernel

Definition at line 120 of file CombinedKernel.h.

CKernel* get_kernel ( int32_t  idx  ) 

get kernel

Parameters:
idx index of kernel
Returns:
kernel at index idx

Definition at line 130 of file CombinedKernel.h.

virtual EKernelType get_kernel_type (  )  [virtual]

return what type of kernel we are

Returns:
kernel type COMBINED

Implements CKernel.

Definition at line 74 of file CombinedKernel.h.

CKernel* get_last_kernel (  ) 

get last kernel

Returns:
last kernel

Definition at line 145 of file CombinedKernel.h.

virtual const char* get_name (  )  const [virtual]

return the kernel's name

Returns:
name Combined

Implements CSGObject.

Definition at line 101 of file CombinedKernel.h.

CKernel* get_next_kernel (  ) 

get next kernel

Returns:
next kernel

Definition at line 154 of file CombinedKernel.h.

CKernel* get_next_kernel ( CListElement *&  current  ) 

get next kernel multi-thread safe

Parameters:
current 
Returns:
next kernel

Definition at line 164 of file CombinedKernel.h.

int32_t get_num_subkernels (  )  [virtual]

get number of subkernels

Returns:
number of subkernels

Reimplemented from CKernel.

Definition at line 233 of file CombinedKernel.h.

SGVector< float64_t > get_subkernel_weights (  )  [virtual]

get subkernel weights (swig compatible)

Returns:
subkernel weights

Definition at line 688 of file CombinedKernel.cpp.

const float64_t * get_subkernel_weights ( int32_t &  num_weights  )  [virtual]

get subkernel weights

Parameters:
num_weights where number of weights is stored
Returns:
subkernel weights

Reimplemented from CKernel.

Definition at line 646 of file CombinedKernel.cpp.

virtual bool has_features (  )  [virtual]

test whether features have been assigned to lhs and rhs

Returns:
true if features are assigned

Reimplemented from CKernel.

Definition at line 257 of file CombinedKernel.h.

bool init ( CFeatures *  lhs,
CFeatures *  rhs 
) [virtual]

initialize kernel

Parameters:
lhs features of left-hand side
rhs features of right-hand side
Returns:
if initializing was successful

Reimplemented from CKernel.

Definition at line 67 of file CombinedKernel.cpp.

bool init_optimization ( int32_t  count,
int32_t *  IDX,
float64_t *  weights 
) [virtual]

initialize optimization

Parameters:
count count
IDX index
weights weights
Returns:
if initializing was successful

Reimplemented from CKernel.

Definition at line 259 of file CombinedKernel.cpp.

bool insert_kernel ( CKernel *  k  ) 

insert kernel

Parameters:
k kernel
Returns:
if inserting was successful

Definition at line 174 of file CombinedKernel.h.

CCombinedKernel* KernelToCombinedKernel ( shogun::CKernel *  n  ) 

casts kernel to combined kernel

Parameters:
n kernel to cast

Definition at line 380 of file CombinedKernel.h.

void list_kernels (  ) 

list kernels

Definition at line 225 of file CombinedKernel.cpp.

bool precompute_subkernels (  ) 

precompute all sub-kernels

Definition at line 746 of file CombinedKernel.cpp.

void remove_lhs (  )  [virtual]

remove lhs from kernel

Reimplemented from CKernel.

Definition at line 147 of file CombinedKernel.cpp.

void remove_lhs_and_rhs (  )  [virtual]

remove lhs and rhs from kernel

Reimplemented from CKernel.

Definition at line 184 of file CombinedKernel.cpp.

void remove_rhs (  )  [virtual]

remove rhs from kernel

Reimplemented from CKernel.

Definition at line 167 of file CombinedKernel.cpp.

void set_optimization_type ( EOptimizationType  t  )  [virtual]

set optimization type

Parameters:
t optimization type

Reimplemented from CKernel.

Definition at line 731 of file CombinedKernel.cpp.

void set_subkernel_weights ( SGVector< float64_t >  weights  )  [virtual]

set subkernel weights

Parameters:
weights new subkernel weights

Reimplemented from CKernel.

Definition at line 696 of file CombinedKernel.cpp.

Member Data Documentation

bool append_subkernel_weights [protected]

if subkernel weights are appended

Definition at line 453 of file CombinedKernel.h.

bool initialized [protected]

whether kernel is ready to be used

Definition at line 455 of file CombinedKernel.h.

CList* kernel_list [protected]

list of kernels

Definition at line 443 of file CombinedKernel.h.

float64_t* subkernel_weights_buffer [protected]

subkernel weights buffers

Definition at line 451 of file CombinedKernel.h.

int32_t sv_count [protected]

support vector count

Definition at line 445 of file CombinedKernel.h.

int32_t* sv_idx [protected]

support vector index

Definition at line 447 of file CombinedKernel.h.

float64_t* sv_weight [protected]

support vector weights

Definition at line 449 of file CombinedKernel.h.

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