CGaussianShiftKernel Class Reference
Detailed Description
An experimental kernel inspired by the WeightedDegreePositionStringKernel and the Gaussian kernel. It is computed as
![\[ k({\bf x},{\bf x'})= \exp(-\frac{||{\bf x}-{\bf x'}||^2}{\tau}) + \sum_{s=1}^{S_{\mathrm{max}}/S_{\mathrm{step}}} \frac{1}{2s} \exp(-\frac{||{\bf x}_{[1:|{\bf x}|-sS_{\mathrm{step}}]}-{\bf x'}_{[sS_{\mathrm{step}}:|{\bf x}|]}||^2}{\tau}) + \sum_{s=1}^{S_{max}/S_{step}} \frac{1}{2s} \exp(-\frac{||{\bf x}_{[sS_{\mathrm{step}}:|{\bf x}|]}-{\bf x'}_{[1:|{\bf x}|-sS_{\mathrm{step}}]}||^2}{\tau}) + \]](form_55.png)
where 
is the kernel width. The idea is to shift the dimensions of the input vectors against eachother. 
is the step size (parameter shift_step) of the shifts and 
(parameter max_shift) is the maximal shift.
Definition at line 32 of file GaussianShiftKernel.h.
Public Member Functions | |
| CGaussianShiftKernel (int32_t size, float64_t width, int32_t max_shift, int32_t shift_step) | |
| CGaussianShiftKernel (CRealFeatures *l, CRealFeatures *r, float64_t width, int32_t max_shift, int32_t shift_step, int32_t size=10) | |
| virtual | ~CGaussianShiftKernel () |
| virtual EKernelType | get_kernel_type () |
| virtual const char * | get_name () |
Protected Member Functions | |
| virtual float64_t | compute (int32_t idx_a, int32_t idx_b) |
Protected Attributes | |
| int32_t | max_shift |
| int32_t | shift_step |
Constructor & Destructor Documentation
| CGaussianShiftKernel::CGaussianShiftKernel | ( | int32_t | size, | |
| float64_t | width, | |||
| int32_t | max_shift, | |||
| int32_t | shift_step | |||
| ) |
constructor
- Parameters:
-
size cache size width width max_shift maximum shift shift_step shift step
Definition at line 17 of file GaussianShiftKernel.cpp.
| CGaussianShiftKernel::CGaussianShiftKernel | ( | CRealFeatures * | l, | |
| CRealFeatures * | r, | |||
| float64_t | width, | |||
| int32_t | max_shift, | |||
| int32_t | shift_step, | |||
| int32_t | size = 10 | |||
| ) |
constructor
- Parameters:
-
l features of left-hand side r features of right-hand side width width max_shift maximum shift shift_step shift step size cache size
Definition at line 23 of file GaussianShiftKernel.cpp.
| CGaussianShiftKernel::~CGaussianShiftKernel | ( | ) | [virtual] |
Definition at line 31 of file GaussianShiftKernel.cpp.
Member Function Documentation
| virtual EKernelType CGaussianShiftKernel::get_kernel_type | ( | ) | [virtual] |
return what type of kernel we are
- Returns:
- kernel type GAUSSIANSHIFT
Reimplemented from CGaussianKernel.
Definition at line 66 of file GaussianShiftKernel.h.
| virtual const char* CGaussianShiftKernel::get_name | ( | ) | [virtual] |
return the kernel's name
- Returns:
- name GaussianShift
Reimplemented from CGaussianKernel.
Definition at line 72 of file GaussianShiftKernel.h.
| float64_t CGaussianShiftKernel::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
- Parameters:
-
idx_a index a idx_b index b
- Returns:
- computed kernel function at indices a,b
Reimplemented from CGaussianKernel.
Definition at line 35 of file GaussianShiftKernel.cpp.
Member Data Documentation
int32_t CGaussianShiftKernel::max_shift [protected] |
maximum shift
Definition at line 87 of file GaussianShiftKernel.h.
int32_t CGaussianShiftKernel::shift_step [protected] |
shift step
Definition at line 89 of file GaussianShiftKernel.h.
The documentation for this class was generated from the following files: