SHOGUN
v1.1.0
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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) 2009 Soeren Sonnenburg 00008 * Copyright (C) 2009 Fraunhofer Institute FIRST and Max-Planck-Society 00009 */ 00010 00011 #include <shogun/lib/common.h> 00012 #include <shogun/mathematics/Math.h> 00013 #include <shogun/kernel/TensorProductPairKernel.h> 00014 #include <shogun/features/SimpleFeatures.h> 00015 #include <shogun/io/SGIO.h> 00016 00017 using namespace shogun; 00018 00019 CTensorProductPairKernel::CTensorProductPairKernel() 00020 : CDotKernel(0), subkernel(NULL) 00021 { 00022 register_params(); 00023 } 00024 00025 CTensorProductPairKernel::CTensorProductPairKernel(int32_t size, CKernel* s) 00026 : CDotKernel(size), subkernel(s) 00027 { 00028 SG_REF(subkernel); 00029 register_params(); 00030 } 00031 00032 CTensorProductPairKernel::CTensorProductPairKernel(CSimpleFeatures<int32_t>* l, CSimpleFeatures<int32_t>* r, CKernel* s) 00033 : CDotKernel(10), subkernel(s) 00034 { 00035 SG_REF(subkernel); 00036 init(l, r); 00037 register_params(); 00038 } 00039 00040 CTensorProductPairKernel::~CTensorProductPairKernel() 00041 { 00042 SG_UNREF(subkernel); 00043 cleanup(); 00044 } 00045 00046 bool CTensorProductPairKernel::init(CFeatures* l, CFeatures* r) 00047 { 00048 CDotKernel::init(l, r); 00049 init_normalizer(); 00050 return true; 00051 } 00052 00053 float64_t CTensorProductPairKernel::compute(int32_t idx_a, int32_t idx_b) 00054 { 00055 int32_t alen, blen; 00056 bool afree, bfree; 00057 00058 int32_t* avec=((CSimpleFeatures<int32_t>*) lhs)->get_feature_vector(idx_a, alen, afree); 00059 int32_t* bvec=((CSimpleFeatures<int32_t>*) rhs)->get_feature_vector(idx_b, blen, bfree); 00060 00061 ASSERT(alen==2); 00062 ASSERT(blen==2); 00063 00064 CKernel* k=subkernel; 00065 ASSERT(k && k->has_features()); 00066 00067 int32_t a=avec[0]; 00068 int32_t b=avec[1]; 00069 int32_t c=bvec[0]; 00070 int32_t d=bvec[1]; 00071 00072 float64_t result = k->kernel(a,c)*k->kernel(b,d) + k->kernel(a,d)*k->kernel(b,c); 00073 00074 ((CSimpleFeatures<int32_t>*) lhs)->free_feature_vector(avec, idx_a, afree); 00075 ((CSimpleFeatures<int32_t>*) rhs)->free_feature_vector(bvec, idx_b, bfree); 00076 00077 return result; 00078 } 00079 00080 void CTensorProductPairKernel::register_params() 00081 { 00082 m_parameters->add((CSGObject**)&subkernel, "subkernel", "the subkernel"); 00083 }