Computes the Tensor Product Pair Kernel (TPPK).
Formally, it computes
![\[ k_{\mbox{tppk}}(({\bf a},{\bf b}), ({\bf c},{\bf d}))= k({\bf a}, {\bf c})\cdot k({\bf b}, {\bf c}) + k({\bf a},{\bf d})\cdot k({\bf b}, {\bf c}) \]](form_165.png)
It is defined on pairs of inputs and a subkernel 
. The subkernel has to be given on initialization. The pairs are specified via indizes (ab)using 2-dimensional integer features.
Its feature space 
is the tensor product of the feature spaces of the subkernel 
on its input.
It is often used in bioinformatics, e.g., to predict protein-protein interactions.
Definition at line 37 of file TensorProductPairKernel.h.
Public Member Functions | |
| CTensorProductPairKernel () | |
| CTensorProductPairKernel (int32_t size, CKernel *subkernel) | |
| CTensorProductPairKernel (CSimpleFeatures< int32_t > *l, CSimpleFeatures< int32_t > *r, CKernel *subkernel) | |
| virtual | ~CTensorProductPairKernel () |
| virtual bool | init (CFeatures *l, CFeatures *r) |
| virtual EKernelType | get_kernel_type () |
| virtual void | register_params () |
| virtual const char * | get_name () const |
| virtual EFeatureClass | get_feature_class () |
| virtual EFeatureType | get_feature_type () |
Protected Member Functions | |
| virtual float64_t | compute (int32_t idx_a, int32_t idx_b) |
Protected Attributes | |
| CKernel * | subkernel |
default constructor
Definition at line 19 of file TensorProductPairKernel.cpp.
| CTensorProductPairKernel | ( | int32_t | size, | |
| CKernel * | subkernel | |||
| ) |
constructor
| size | cache size | |
| subkernel | the subkernel |
Definition at line 25 of file TensorProductPairKernel.cpp.
| CTensorProductPairKernel | ( | CSimpleFeatures< int32_t > * | l, | |
| CSimpleFeatures< int32_t > * | r, | |||
| CKernel * | subkernel | |||
| ) |
constructor
| l | features of left-hand side | |
| r | features of right-hand side | |
| subkernel | the subkernel |
Definition at line 32 of file TensorProductPairKernel.cpp.
| ~CTensorProductPairKernel | ( | ) | [virtual] |
Definition at line 40 of file TensorProductPairKernel.cpp.
| float64_t compute | ( | int32_t | idx_a, | |
| int32_t | idx_b | |||
| ) | [protected, virtual] |
compute kernel function for features a and b idx_{a,b} denote the index of the feature vectors in the corresponding feature object
| idx_a | index a | |
| idx_b | index b |
Reimplemented from CDotKernel.
Definition at line 53 of file TensorProductPairKernel.cpp.
| virtual EFeatureClass get_feature_class | ( | ) | [virtual] |
return feature class the kernel can deal with
Reimplemented from CDotKernel.
Definition at line 88 of file TensorProductPairKernel.h.
| virtual EFeatureType get_feature_type | ( | ) | [virtual] |
return feature type the kernel can deal with
Reimplemented from CDotKernel.
Definition at line 94 of file TensorProductPairKernel.h.
| virtual EKernelType get_kernel_type | ( | ) | [virtual] |
return what type of kernel we are
Implements CDotKernel.
Definition at line 72 of file TensorProductPairKernel.h.
| virtual const char* get_name | ( | ) | const [virtual] |
return the kernel's name
Reimplemented from CDotKernel.
Definition at line 82 of file TensorProductPairKernel.h.
initialize kernel
| l | features of left-hand side | |
| r | features of right-hand side |
Reimplemented from CDotKernel.
Definition at line 46 of file TensorProductPairKernel.cpp.
| void register_params | ( | ) | [virtual] |
Separate the function of parameter registration This can be the first stage of a *general* framework for cross-validation or other parameter-based operations
Reimplemented from CKernel.
Definition at line 80 of file TensorProductPairKernel.cpp.
the subkernel
Definition at line 109 of file TensorProductPairKernel.h.
