Kernel function that uses a Model as transformation function for another kernel. More...

#include <shark/Models/Kernels/ModelKernel.h>

Inheritance diagram for shark::ModelKernel< InputType >:

Public Types
typedef base_type::BatchInputType	BatchInputType

typedef base_type::ConstInputReference	ConstInputReference

typedef base_type::ConstBatchInputReference	ConstBatchInputReference

Public Types inherited from shark::AbstractKernelFunction< InputTypeT >
enum	Feature { HAS_FIRST_PARAMETER_DERIVATIVE = 1 , HAS_FIRST_INPUT_DERIVATIVE = 2 , IS_NORMALIZED = 4 , SUPPORTS_VARIABLE_INPUT_SIZE = 8 }
	enumerations of kerneland metric features (flags) More...

typedef base_type::InputType	InputType
	Input type of the Kernel.

typedef base_type::BatchInputType	BatchInputType
	batch input type of the kernel

typedef base_type::ConstInputReference	ConstInputReference
	Const references to InputType.

typedef base_type::ConstBatchInputReference	ConstBatchInputReference
	Const references to BatchInputType.

typedef TypedFlags< Feature >	Features
	This statement declares the member m_features. See Core/Flags.h for details.

typedef TypedFeatureNotAvailableException< Feature >	FeatureNotAvailableException

Public Types inherited from shark::AbstractMetric< InputTypeT >
typedef InputTypeT	InputType
	Input type of the Kernel.

typedef Batch< InputTypeT >::type	BatchInputType
	batch input type of the kernel

typedef ConstProxyReference< InputTypeconst >::type	ConstInputReference
	Const references to InputType.

typedef ConstProxyReference< BatchInputTypeconst >::type	ConstBatchInputReference
	Const references to BatchInputType.

Public Types inherited from shark::IParameterizable< VectorType >
typedef VectorType	ParameterVectorType

Public Member Functions
template<class IntermediateType >
	ModelKernel (AbstractKernelFunction< IntermediateType > kernel, AbstractModel< InputType, IntermediateType > model)

std::string	name () const
	From INameable: return the class name.

std::size_t	numberOfParameters () const
	Returns the number of parameters.

RealVector	parameterVector () const
	Returns the concatenated parameters of kernel and model.

void	setParameterVector (RealVector const &newParameters)
	Sets the concatenated parameters of kernel and model.

boost::shared_ptr< State >	createState () const
	Returns the internal state object used for eval and the derivatives.

double	eval (ConstInputReference x1, ConstInputReference x2) const
	Computes K(x,y) for a single input pair.

void	eval (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2, RealMatrix &result, State &state) const
	For two batches X1 and X2 computes the matrix k_ij=K(X1_i,X2_j) and stores the state for the derivatives.

void	eval (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2, RealMatrix &result) const
	For two batches X1 and X2 computes the matrix k_ij=K(X1_i,X2_j).

void	weightedParameterDerivative (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2, RealMatrix const &coefficients, State const &state, RealVector &gradient) const
	After a call to eval with state, computes the derivative wrt all parameters of the kernel and the model.

void	write (OutArchive &ar) const
	Stores the kernel to an Archive.

void	read (OutArchive &ar) const
	Reads the kernel from an Archive.

Public Member Functions inherited from shark::AbstractKernelFunction< InputTypeT >
	AbstractKernelFunction ()

const Features &	features () const

virtual void	updateFeatures ()

bool	hasFirstParameterDerivative () const

bool	hasFirstInputDerivative () const

bool	isNormalized () const

bool	supportsVariableInputSize () const

virtual double	eval (ConstInputReference x1, ConstInputReference x2) const
	Evaluates the kernel function.

double	operator() (ConstInputReference x1, ConstInputReference x2) const
	Convenience operator which evaluates the kernel function.

virtual void	eval (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2, RealMatrix &result, State &state) const =0
	Evaluates the subset of the KernelGram matrix which is defined by X1(rows) and X2 (columns).

virtual void	eval (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2, RealMatrix &result) const
	Evaluates the subset of the KernelGram matrix which is defined by X1(rows) and X2 (columns).

RealMatrix	operator() (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2) const
	Evaluates the subset of the KernelGram matrix which is defined by X1(rows) and X2 (columns).

virtual void	weightedParameterDerivative (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2, RealMatrix const &coefficients, State const &state, RealVector &gradient) const
	Computes the gradient of the parameters as a weighted sum over the gradient of all elements of the batch.

virtual void	weightedInputDerivative (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2, RealMatrix const &coefficientsX2, State const &state, BatchInputType &gradient) const
	Calculates the derivative of the inputs X1 (only x1!).

virtual double	featureDistanceSqr (ConstInputReference x1, ConstInputReference x2) const
	Computes the squared distance in the kernel induced feature space.

virtual RealMatrix	featureDistanceSqr (ConstBatchInputReference batchX1, ConstBatchInputReference batchX2) const
	Computes the squared distance in the kernel induced feature space.

Public Member Functions inherited from shark::AbstractMetric< InputTypeT >
	AbstractMetric ()

virtual	~AbstractMetric ()

virtual void	read (InArchive &archive)
	From ISerializable, reads a metric from an archive.

double	featureDistance (ConstInputReference x1, ConstInputReference x2) const
	Computes the distance in the kernel induced feature space.

Public Member Functions inherited from shark::INameable
virtual	~INameable ()

Public Member Functions inherited from shark::IParameterizable< VectorType >
virtual	~IParameterizable ()

Public Member Functions inherited from shark::ISerializable
virtual	~ISerializable ()
	Virtual d'tor.

void	load (InArchive &archive, unsigned int version)
	Versioned loading of components, calls read(...).

void	save (OutArchive &archive, unsigned int version) const
	Versioned storing of components, calls write(...).

	BOOST_SERIALIZATION_SPLIT_MEMBER ()

Additional Inherited Members
Protected Attributes inherited from shark::AbstractKernelFunction< InputTypeT >
Features	m_features

Detailed Description

template<class InputType = RealVector>
class shark::ModelKernel< InputType >

Kernel function that uses a Model as transformation function for another kernel.

Using an Abstractmodel \( f: X \rightarrow X' \) and an inner kernel \(k: X' \times X' \rightarrow \mathbb{R} \), this class defines another kernel \(K: X \times X \rightarrow \mathbb{R}\) using

\[ K(x,y) = k(f(x),f(y)) \]

If the inner kernel \(k\) suports both input, as well as parameter derivative and the model also supports the parameter derivative, the kernel \(K\) also supports the first parameter derivative using

\[ \frac{\partial}{\partial \theta} K(x,y) = \frac{\partial}{\partial f(x)} k(f(x),f(y))\frac{\partial}{\partial \theta} f(x) +\frac{\partial}{\partial f(y)} k(f(x),f(y))\frac{\partial}{\partial \theta} f(y) \]

This requires the derivative of the inputs of the kernel wrt both parameters which, by limitation of the current kernel interface, requires to compute \(k(f(x),f(y))\) and \(k(f(y),f(x))\).

Definition at line 198 of file ModelKernel.h.

Member Typedef Documentation

◆ BatchInputType

template<class InputType = RealVector>

typedef base_type::BatchInputType shark::ModelKernel< InputType >::BatchInputType

Definition at line 202 of file ModelKernel.h.

◆ ConstBatchInputReference

template<class InputType = RealVector>

typedef base_type::ConstBatchInputReference shark::ModelKernel< InputType >::ConstBatchInputReference

Definition at line 204 of file ModelKernel.h.

◆ ConstInputReference

template<class InputType = RealVector>

typedef base_type::ConstInputReference shark::ModelKernel< InputType >::ConstInputReference

Definition at line 203 of file ModelKernel.h.

Constructor & Destructor Documentation

◆ ModelKernel()

template<class InputType = RealVector>

template<class IntermediateType >

shark::ModelKernel< InputType >::ModelKernel	(	AbstractKernelFunction< IntermediateType > *	kernel,
		AbstractModel< InputType, IntermediateType > *	model
	)

inline

Definition at line 207 of file ModelKernel.h.

References shark::AbstractKernelFunction< InputType >::HAS_FIRST_PARAMETER_DERIVATIVE, shark::AbstractKernelFunction< InputTypeT >::m_features, and SHARK_RUNTIME_CHECK.

Member Function Documentation

◆ createState()

template<class InputType = RealVector>

boost::shared_ptr< State > shark::ModelKernel< InputType >::createState ( ) const

inlinevirtual

Returns the internal state object used for eval and the derivatives.

Reimplemented from shark::AbstractKernelFunction< InputTypeT >.

Definition at line 235 of file ModelKernel.h.

◆ eval() [1/3]

template<class InputType = RealVector>

void shark::ModelKernel< InputType >::eval	(	ConstBatchInputReference	batchX1,
		ConstBatchInputReference	batchX2,
		RealMatrix &	result
	)		const

inline

For two batches X1 and X2 computes the matrix k_ij=K(X1_i,X2_j).

Definition at line 249 of file ModelKernel.h.

◆ eval() [2/3]

template<class InputType = RealVector>

void shark::ModelKernel< InputType >::eval	(	ConstBatchInputReference	batchX1,
		ConstBatchInputReference	batchX2,
		RealMatrix &	result,
		State &	state
	)		const

inline

For two batches X1 and X2 computes the matrix k_ij=K(X1_i,X2_j) and stores the state for the derivatives.

Definition at line 245 of file ModelKernel.h.

◆ eval() [3/3]

template<class InputType = RealVector>

double shark::ModelKernel< InputType >::eval	(	ConstInputReference	x1,
		ConstInputReference	x2
	)		const

inline

Computes K(x,y) for a single input pair.

Definition at line 240 of file ModelKernel.h.

◆ name()

template<class InputType = RealVector>

std::string shark::ModelKernel< InputType >::name ( ) const

inlinevirtual

From INameable: return the class name.

Reimplemented from shark::INameable.

Definition at line 218 of file ModelKernel.h.

◆ numberOfParameters()

template<class InputType = RealVector>

std::size_t shark::ModelKernel< InputType >::numberOfParameters ( ) const

inlinevirtual

Returns the number of parameters.

Reimplemented from shark::IParameterizable< VectorType >.

Definition at line 222 of file ModelKernel.h.

◆ parameterVector()

template<class InputType = RealVector>

RealVector shark::ModelKernel< InputType >::parameterVector ( ) const

inlinevirtual

Returns the concatenated parameters of kernel and model.

Reimplemented from shark::IParameterizable< VectorType >.

Definition at line 226 of file ModelKernel.h.

◆ read()

template<class InputType = RealVector>

void shark::ModelKernel< InputType >::read ( OutArchive & ar ) const

inline

Reads the kernel from an Archive.

Definition at line 272 of file ModelKernel.h.

◆ setParameterVector()

template<class InputType = RealVector>

void shark::ModelKernel< InputType >::setParameterVector ( RealVector const & newParameters )

inlinevirtual

Sets the concatenated parameters of kernel and model.

Reimplemented from shark::IParameterizable< VectorType >.

Definition at line 230 of file ModelKernel.h.

◆ weightedParameterDerivative()

template<class InputType = RealVector>

void shark::ModelKernel< InputType >::weightedParameterDerivative	(	ConstBatchInputReference	batchX1,
		ConstBatchInputReference	batchX2,
		RealMatrix const &	coefficients,
		State const &	state,
		RealVector &	gradient
	)		const

inline

After a call to eval with state, computes the derivative wrt all parameters of the kernel and the model.

This is computed over the whole kernel matrix k_ij created by eval and summed up using the coefficients c thus this call returns \( \sum_{i,j} c_{ij} \frac{\partial}{\partial \theta} k(x^1_i,x^2_j)\).

Definition at line 257 of file ModelKernel.h.

◆ write()

template<class InputType = RealVector>

void shark::ModelKernel< InputType >::write ( OutArchive & ar ) const

inlinevirtual

Stores the kernel to an Archive.

Reimplemented from shark::AbstractMetric< InputTypeT >.

Definition at line 268 of file ModelKernel.h.

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

include/shark/Models/Kernels/ModelKernel.h

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ BatchInputType

◆ ConstBatchInputReference

◆ ConstInputReference

Constructor & Destructor Documentation

◆ ModelKernel()

Member Function Documentation

◆ createState()

◆ eval() [1/3]

◆ eval() [2/3]

◆ eval() [3/3]

◆ name()

◆ numberOfParameters()

◆ parameterVector()

◆ read()

◆ setParameterVector()

◆ weightedParameterDerivative()

◆ write()