LibSVMOneClass.cpp
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00012 #include "classifier/svm/LibSVMOneClass.h"
00013 #include "lib/io.h"
00014
00015 CLibSVMOneClass::CLibSVMOneClass()
00016 : CSVM(), model(NULL)
00017 {
00018 }
00019
00020 CLibSVMOneClass::CLibSVMOneClass(DREAL C, CKernel* k)
00021 : CSVM(C, k, NULL), model(NULL)
00022 {
00023 }
00024
00025 CLibSVMOneClass::~CLibSVMOneClass()
00026 {
00027 free(model);
00028 }
00029
00030 bool CLibSVMOneClass::train()
00031 {
00032 ASSERT(kernel);
00033 problem.l=kernel->get_num_vec_lhs();
00034
00035 struct svm_node* x_space;
00036 SG_INFO("%d train data points\n", problem.l);
00037
00038 problem.y=NULL;
00039 problem.x=new struct svm_node*[problem.l];
00040 x_space=new struct svm_node[2*problem.l];
00041
00042 for (int i=0; i<problem.l; i++)
00043 {
00044 problem.x[i]=&x_space[2*i];
00045 x_space[2*i].index=i;
00046 x_space[2*i+1].index=-1;
00047 }
00048
00049 int weights_label[2]={-1,+1};
00050 double weights[2]={1.0,get_C2()/get_C1()};
00051
00052
00053 param.svm_type=ONE_CLASS;
00054 param.kernel_type = LINEAR;
00055 param.degree = 3;
00056 param.gamma = 0;
00057 param.coef0 = 0;
00058 param.nu = get_nu();
00059 param.kernel=kernel;
00060 param.cache_size = kernel->get_cache_size();
00061 param.C = get_C1();
00062 param.eps = epsilon;
00063 param.p = 0.1;
00064 param.shrinking = 1;
00065 param.nr_weight = 2;
00066 param.weight_label = weights_label;
00067 param.weight = weights;
00068
00069 const char* error_msg = svm_check_parameter(&problem,¶m);
00070
00071 if(error_msg)
00072 {
00073 fprintf(stderr,"Error: %s\n",error_msg);
00074 exit(1);
00075 }
00076
00077 model = svm_train(&problem, ¶m);
00078
00079 if (model)
00080 {
00081 ASSERT(model->nr_class==2);
00082 ASSERT((model->l==0) || (model->l>0 && model->SV && model->sv_coef && model->sv_coef[0]));
00083
00084 int num_sv=model->l;
00085
00086 create_new_model(num_sv);
00087 CSVM::set_objective(model->objective);
00088
00089 set_bias(-model->rho[0]);
00090 for (int i=0; i<num_sv; i++)
00091 {
00092 set_support_vector(i, (model->SV[i])->index);
00093 set_alpha(i, model->sv_coef[0][i]);
00094 }
00095
00096 delete[] problem.x;
00097 delete[] x_space;
00098 svm_destroy_model(model);
00099 model=NULL;
00100
00101 return true;
00102 }
00103 else
00104 return false;
00105 }