GaussianKernel.cpp
Go to the documentation of this file.00001
00002
00003
00004
00005
00006
00007
00008
00009
00010
00011 #include "lib/common.h"
00012 #include "kernel/GaussianKernel.h"
00013 #include "features/Features.h"
00014 #include "features/RealFeatures.h"
00015 #include "lib/io.h"
00016
00017 CGaussianKernel::CGaussianKernel(INT size, DREAL w)
00018 : CSimpleKernel<DREAL>(size), width(w)
00019 {
00020 }
00021
00022 CGaussianKernel::CGaussianKernel(
00023 CRealFeatures* l, CRealFeatures* r, DREAL w, INT size)
00024 : CSimpleKernel<DREAL>(size), width(w)
00025 {
00026 init(l,r);
00027 }
00028
00029 CGaussianKernel::~CGaussianKernel()
00030 {
00031 }
00032
00033 bool CGaussianKernel::init(CFeatures* l, CFeatures* r)
00034 {
00035 CSimpleKernel<DREAL>::init(l, r);
00036 return true;
00037 }
00038
00039 bool CGaussianKernel::load_init(FILE* src)
00040 {
00041 return false;
00042 }
00043
00044 bool CGaussianKernel::save_init(FILE* dest)
00045 {
00046 return false;
00047 }
00048
00049 DREAL CGaussianKernel::compute(INT idx_a, INT idx_b)
00050 {
00051 INT alen, blen;
00052 bool afree, bfree;
00053
00054 DREAL* avec=((CRealFeatures*) lhs)->get_feature_vector(idx_a, alen, afree);
00055 DREAL* bvec=((CRealFeatures*) rhs)->get_feature_vector(idx_b, blen, bfree);
00056 ASSERT(alen==blen);
00057
00058 DREAL result=0;
00059 for (INT i=0; i<alen; i++)
00060 result+=CMath::sq(avec[i]-bvec[i]);
00061
00062 result=exp(-result/width);
00063
00064 ((CRealFeatures*) lhs)->free_feature_vector(avec, idx_a, afree);
00065 ((CRealFeatures*) rhs)->free_feature_vector(bvec, idx_b, bfree);
00066
00067 return result;
00068 }