ChiSquareDistance.cpp
Go to the documentation of this file.00001
00002
00003
00004
00005
00006
00007
00008
00009
00010
00011 #include "lib/config.h"
00012 #include "lib/common.h"
00013 #include "lib/io.h"
00014 #include "distance/ChiSquareDistance.h"
00015 #include "features/Features.h"
00016 #include "features/RealFeatures.h"
00017
00018 CChiSquareDistance::CChiSquareDistance()
00019 : CSimpleDistance<float64_t>()
00020 {
00021 }
00022
00023 CChiSquareDistance::CChiSquareDistance(CRealFeatures* l, CRealFeatures* r)
00024 : CSimpleDistance<float64_t>()
00025 {
00026 init(l, r);
00027 }
00028
00029 CChiSquareDistance::~CChiSquareDistance()
00030 {
00031 cleanup();
00032 }
00033
00034 bool CChiSquareDistance::init(CFeatures* l, CFeatures* r)
00035 {
00036 bool result=CSimpleDistance<float64_t>::init(l,r);
00037
00038 return result;
00039 }
00040
00041 void CChiSquareDistance::cleanup()
00042 {
00043 }
00044
00045 bool CChiSquareDistance::load_init(FILE* src)
00046 {
00047 return false;
00048 }
00049
00050 bool CChiSquareDistance::save_init(FILE* dest)
00051 {
00052 return false;
00053 }
00054
00055 float64_t CChiSquareDistance::compute(int32_t idx_a, int32_t idx_b)
00056 {
00057 int32_t alen, blen;
00058 bool afree, bfree;
00059
00060 float64_t* avec=
00061 ((CRealFeatures*) lhs)->get_feature_vector(idx_a, alen, afree);
00062 float64_t* bvec=
00063 ((CRealFeatures*) rhs)->get_feature_vector(idx_b, blen, bfree);
00064
00065 ASSERT(alen==blen);
00066
00067 float64_t absTmp = 0;
00068 float64_t result=0;
00069 {
00070 for (int32_t i=0; i<alen; i++)
00071 {
00072 absTmp=fabs(avec[i])+fabs(bvec[i]);
00073 if(absTmp!=0)
00074 result+=pow((avec[i]-bvec[i]),2)/absTmp;
00075 }
00076
00077 }
00078
00079 ((CRealFeatures*) lhs)->free_feature_vector(avec, idx_a, afree);
00080 ((CRealFeatures*) rhs)->free_feature_vector(bvec, idx_b, bfree);
00081
00082 return result;
00083 }