PluginEstimate.h

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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) 1999-2008 Soeren Sonnenburg
00008  * Copyright (C) 1999-2008 Fraunhofer Institute FIRST and Max-Planck-Society
00009  */
00010 
00011 #ifndef _PLUGINESTIMATE_H___
00012 #define _PLUGINESTIMATE_H___
00013 
00014 #include "classifier/Classifier.h"
00015 #include "features/StringFeatures.h"
00016 #include "features/Labels.h"
00017 #include "distributions/hmm/LinearHMM.h"
00018 
00020 class CPluginEstimate: public CClassifier
00021 {
00022     public:
00027         CPluginEstimate(float64_t pos_pseudo=1e-10, float64_t neg_pseudo=1e-10);
00028         virtual ~CPluginEstimate();
00029 
00034         bool train();
00035 
00037         CLabels* classify(CLabels* output=NULL);
00038 
00043         virtual inline void set_features(CStringFeatures<uint16_t>* feat)
00044         {
00045             SG_UNREF(features);
00046             SG_REF(feat);
00047             features=feat;
00048         }
00049 
00054         virtual CStringFeatures<uint16_t>* get_features() { SG_REF(features); return features; }
00055 
00057         float64_t classify_example(int32_t vec_idx);
00058 
00065         inline float64_t posterior_log_odds_obsolete(
00066             uint16_t* vector, int32_t len)
00067         {
00068             return pos_model->get_log_likelihood_example(vector, len) - neg_model->get_log_likelihood_example(vector, len);
00069         }
00070 
00077         inline float64_t get_parameterwise_log_odds(
00078             uint16_t obs, int32_t position)
00079         {
00080             return pos_model->get_positional_log_parameter(obs, position) - neg_model->get_positional_log_parameter(obs, position);
00081         }
00082 
00089         inline float64_t log_derivative_pos_obsolete(uint16_t obs, int32_t pos)
00090         {
00091             return pos_model->get_log_derivative_obsolete(obs, pos);
00092         }
00093 
00100         inline float64_t log_derivative_neg_obsolete(uint16_t obs, int32_t pos)
00101         {
00102             return neg_model->get_log_derivative_obsolete(obs, pos);
00103         }
00104 
00113         inline bool get_model_params(
00114             float64_t*& pos_params, float64_t*& neg_params,
00115             int32_t &seq_length, int32_t &num_symbols)
00116         {
00117             int32_t num;
00118 
00119             if ((!pos_model) || (!neg_model))
00120             {
00121                 SG_ERROR( "no model available\n");
00122                 return false;
00123             }
00124 
00125             pos_model->get_log_transition_probs(&pos_params, &num);
00126             neg_model->get_log_transition_probs(&neg_params, &num);
00127 
00128             seq_length = pos_model->get_sequence_length();
00129             num_symbols = pos_model->get_num_symbols();
00130             ASSERT(pos_model->get_num_model_parameters()==neg_model->get_num_model_parameters());
00131             ASSERT(pos_model->get_num_symbols()==neg_model->get_num_symbols());
00132             return true;
00133         }
00134 
00141         inline void set_model_params(
00142             const float64_t* pos_params, const float64_t* neg_params,
00143             int32_t seq_length, int32_t num_symbols)
00144         {
00145             int32_t num_params;
00146 
00147             delete pos_model;
00148             pos_model=new CLinearHMM(seq_length, num_symbols);
00149             delete neg_model;
00150             neg_model=new CLinearHMM(seq_length, num_symbols);
00151 
00152             num_params=pos_model->get_num_model_parameters();
00153             ASSERT(seq_length*num_symbols==num_params);
00154             ASSERT(num_params==neg_model->get_num_model_parameters());
00155 
00156             pos_model->set_log_transition_probs(pos_params, num_params);
00157             neg_model->set_log_transition_probs(neg_params, num_params);
00158         }
00159 
00164         inline int32_t get_num_params()
00165         {
00166             return pos_model->get_num_model_parameters()+neg_model->get_num_model_parameters();
00167         }
00168         
00173         inline bool check_models()
00174         {
00175             return ( (pos_model!=NULL) && (neg_model!=NULL) );
00176         }
00177 
00178     protected:
00180         float64_t m_pos_pseudo;
00182         float64_t m_neg_pseudo;
00183 
00185         CLinearHMM* pos_model;
00187         CLinearHMM* neg_model;
00188 
00190         CStringFeatures<uint16_t>* features;
00191 };
00192 #endif

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