/**   rankboost.h: efficiently implement the RankBoost    algorithm (Freund et al. 2003) for ordinal regression   (c) 2006-2007 Hsuan-Tien Lin**/#ifndef __LEMGA_AGGRANK_RANKBOOST_H__#define __LEMGA_AGGRANK_RANKBOOST_H__#include "aggrank.h"namespace lemga {  class RankBoost : public AggRank {  protected:    REAL reg_param;  public:    explicit RankBoost (UINT _n_rank = 2): AggRank(_n_rank), reg_param(0.0) { }    explicit RankBoost (std::istream& is) { is >> *this; }    virtual const id_t& id () const;    virtual RankBoost* create () const { return new RankBoost(); }    virtual RankBoost* clone () const { return new RankBoost(*this); }    void set_reg_param(REAL _reg_param) { reg_param = _reg_param; }  public:    virtual void train ();  private:    void update_with_dec(vREAL& rhopos, vREAL& rhoneg, REAL& sum_rhodiff, REAL& obj);    REAL compute_w(pLearnModel plm);  };} // namespace lemga#ifdef  __ADARANK_H__#warning "This header file may conflict with another `adarank.h' file."#endif#define __ADARANK_H__#endif