SHOGUN
v1.1.0
|
00001 /* 00002 * This program is free software; you can redistribute it and/or modify 00003 * it under the terms of the GNU General Public License as published by 00004 * the Free Software Foundation; either version 3 of the License, or 00005 * (at your option) any later version. 00006 * 00007 * Written (W) 2011 Sergey Bartunov 00008 * Copyright (C) 1999-2009 Fraunhofer Institute FIRST and Max-Planck-Society 00009 * Copyright (C) 2010 Berlin Institute of Technology 00010 */ 00011 00012 #include <shogun/lib/config.h> 00013 #include <shogun/lib/common.h> 00014 #include <shogun/io/SGIO.h> 00015 #include <shogun/kernel/SplineKernel.h> 00016 #include <shogun/features/DotFeatures.h> 00017 #include <shogun/features/SimpleFeatures.h> 00018 00019 using namespace shogun; 00020 00021 CSplineKernel::CSplineKernel() : CDotKernel() 00022 { 00023 } 00024 00025 CSplineKernel::CSplineKernel(CDotFeatures* l, CDotFeatures* r) : CDotKernel() 00026 { 00027 init(l,r); 00028 } 00029 00030 CSplineKernel::~CSplineKernel() 00031 { 00032 cleanup(); 00033 } 00034 00035 bool CSplineKernel::init(CFeatures* l, CFeatures* r) 00036 { 00037 ASSERT(l->get_feature_type()==F_DREAL); 00038 ASSERT(l->get_feature_type()==r->get_feature_type()); 00039 00040 ASSERT(l->get_feature_class()==C_SIMPLE); 00041 ASSERT(l->get_feature_class()==r->get_feature_class()); 00042 00043 CDotKernel::init(l,r); 00044 return init_normalizer(); 00045 } 00046 00047 void CSplineKernel::cleanup() 00048 { 00049 CKernel::cleanup(); 00050 } 00051 00052 float64_t CSplineKernel::compute(int32_t idx_a, int32_t idx_b) 00053 { 00054 int32_t alen, blen; 00055 bool afree, bfree; 00056 00057 float64_t* avec = ((CSimpleFeatures<float64_t>*) lhs)->get_feature_vector(idx_a, alen, afree); 00058 float64_t* bvec = ((CSimpleFeatures<float64_t>*) rhs)->get_feature_vector(idx_b, blen, bfree); 00059 ASSERT(alen == blen); 00060 00061 float64_t result = 0; 00062 for (int32_t i = 0; i < alen; i++) { 00063 const float64_t x = avec[i], y = bvec[i]; 00064 const float64_t min = CMath::min(avec[i], bvec[i]); 00065 result += 1 + x*y + x*y*min - ((x+y)/2)*min*min + min*min*min/3; 00066 } 00067 00068 ((CSimpleFeatures<float64_t>*) lhs)->free_feature_vector(avec, idx_a, afree); 00069 ((CSimpleFeatures<float64_t>*) rhs)->free_feature_vector(bvec, idx_b, bfree); 00070 00071 return result; 00072 }