presage  0.8.7
recencyPredictor.h
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00001 
00002 /******************************************************
00003  *  Presage, an extensible predictive text entry system
00004  *  ---------------------------------------------------
00005  *
00006  *  Copyright (C) 2008  Matteo Vescovi <matteo.vescovi@yahoo.co.uk>
00007 
00008     This program is free software; you can redistribute it and/or modify
00009     it under the terms of the GNU General Public License as published by
00010     the Free Software Foundation; either version 2 of the License, or
00011     (at your option) any later version.
00012 
00013     This program is distributed in the hope that it will be useful,
00014     but WITHOUT ANY WARRANTY; without even the implied warranty of
00015     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00016     GNU General Public License for more details.
00017 
00018     You should have received a copy of the GNU General Public License along
00019     with this program; if not, write to the Free Software Foundation, Inc.,
00020     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
00021                                                                              *
00022                                                                 **********(*)*/
00023 
00024 
00025 #ifndef PRESAGE_RECENCYPREDICTOR
00026 #define PRESAGE_RECENCYPREDICTOR
00027 
00028 #include "predictor.h"
00029 #include "../core/logger.h"
00030 #include "../core/dispatcher.h"
00031 
00064 class RecencyPredictor : public Predictor, public Observer {
00065 public:
00066     RecencyPredictor(Configuration*, ContextTracker*);
00067     ~RecencyPredictor();
00068 
00069     virtual Prediction predict(const size_t size, const char** filter) const;
00070 
00071     virtual void learn(const std::vector<std::string>& change);
00072 
00073     virtual void update (const Observable* variable);
00074 
00075 private:
00076     void set_lambda           (const std::string& value);
00077     void set_n_0              (const std::string& value);
00078     void set_cutoff_threshold (const std::string& value);
00079 
00080     static const char* LOGGER;
00081     static const char* LAMBDA;
00082     static const char* N_0;
00083     static const char* CUTOFF_THRESHOLD;
00084     
00085     double lambda;
00086     double n_0;
00087     size_t cutoff_threshold;
00088 
00089     Dispatcher<RecencyPredictor> dispatcher;
00090 
00091 };
00092 
00093 #endif // PRESAGE_RECENCYPREDICTOR