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#ifndef __ALG_UMINALG_H_
#define __ALG_UMINALG_H_

#include "uminstep.hh"

namespace RVLUmin {

  using namespace RVLAlg;
  using RVL::Functional;
  using RVL::Vector;

  template<class Scalar> 
  class UMinAlg : public StateAlg<Vector<Scalar> > {
  public:
    virtual void run() = 0;

    virtual Vector<Scalar> & getState()  = 0;
    virtual Vector<Scalar> const & getState() const  = 0;

  };

  /* temp disabled
  
  template<class Scalar>
  class UMinAlgTR : public UMinAlg<Scalar> {
  private:

    Functional<Scalar> const & f; // objective function 
    UMinDir<Scalar> & dc;         // direction update method
    Vector<Scalar> & x;           // initial estimate on call, solution on return

    // Terminator parameters
    int maxitn;
    Scalar tol;
    int displevel;
    bool dispflag;
    ostream & str;
    
    UMinAlgTR();

  public:
    UMinAlgTR(Functional<Scalar> const & _f,
	      Vector<Scalar> & _x,
	      UMinDir<Scalar> & _dc,
	      int _maxitn = 20,
	      Scalar _tol = 0.01,
	      bool _dispflag = false,
	      ostream & _str = cout
	      )
      : f(_f), x(_x), dc(_dc),
	maxitn(_maxitn),
	tol(_tol),
	dispflag(_dispflag),
        str(_str) {}

    UMinAlgTR(UMinAlgTR<Scalar> const & umin)
      : f(umin.f), x(umin.x), dc(umin.dc),
	maxitn(umin.maxitn),
	tol(umin.tol),
	dispflag(umin.dispflag),
	str(umin.str) {}
	       
    virtual ~UMinAlgTR() {}

    void run() {
      try {
	
	FunctionalEvaluation<Scalar> fx(f,x);
      
	CountingIterationTable<Scalar> 
	  stop(maxitn,
	       //	       tol*fx.getGradient().norm(),
	       tol,
	       fx,
	       dispflag,
	       str);
	
	UMinStepTR<Scalar> step(fx,dc,str);
	LoopAlg Umin(step, stop);
	Umin.run();
      } 
      catch(RVLException & e) {
	e << "called from UMinAlgTR::run()\n";
	throw e;
      } 
      catch( std::exception & e) {
	RVLException es;
	es << "Exception caught in UMinAlgTR::run() with error message";
	es << e.what(); 
	throw e;
      }
      return true;
    } 

    Vector<Scalar> & getState() { return x; }
    Vector<Scalar> const & getState() const { return x; }

    ostream & write(ostream & str) const {
      str<<"UMinAlgTR: unconstrained minimization with TR-CG algorithm\n";
      str<<"Objective function:\n";
      f.write(str);
      str<<"Solution vector:\n";
      x.write(str);
      return str;
    }


  };



  template<class Scalar>
  class UMinAlgLS : public UMinAlg<Scalar> {
  private:

    Functional<Scalar> const & f; // objective function 
    Vector<Scalar> & x;           // initial estimate on call, solution on return
    UMinDir<Scalar> & dc;         // direction update method
    LineSearchAlg<Scalar> & ls;   // line search method

    // Terminator parameters
    int maxitn;
    Scalar tol;
    int displevel;
    bool dispflag;
    ostream & str;
    
    UMinAlgLS();

  public:

    UMinAlgLS(Functional<Scalar> const & _f,
	    Vector<Scalar> & _x,
	    UMinDir<Scalar> & _dc,
	    LineSearchAlg<Scalar> & _ls,
	    int _maxitn = 20,
	    Scalar _tol = 0.01,
	    bool _dispflag = false,
	    ostream & _str = cout
	    )
      : f(_f), x(_x), dc(_dc), ls(_ls),
	maxitn(_maxitn),
	tol(_tol),
	dispflag(_dispflag),
        str(_str) {}

    UMinAlgLS(UMinAlgLS<Scalar> const & umin)
      : f(umin.f), x(umin.x), dc(umin.dc), ls(umin.ls),
	maxitn(umin.maxitn),
	tol(umin.tol),
	dispflag(umin.dispflag),
	str(umin.str) {}
	       
    virtual ~UMinAlgLS() {}

    Vector<Scalar> & getState() { return x; }
    Vector<Scalar> const & getState() const { return x; }

    void run() {
      try {

	FunctionalEvaluation<Scalar> fx(f,x);
	
	CountingIterationTable<Scalar> 
	  stop(maxitn,
	       //	       tol*fx.getGradient().norm(),
	       tol,
	       fx,
	       dispflag,
	       str);

	
	UMinStepLS<Scalar> step(fx,dc,ls,str);

	LoopAlg Umin(step, stop);

	Umin.run();
      } 
      catch(RVLException & e) {
	e << "called from UMinAlgLS::run()\n";
	throw e;
      } 
      catch( std::exception & e) {
	RVLException es;
	es << "Exception caught in UMinAlgLS::run() with error message";
	es << e.what(); 
	throw e;
      }
      return true;
    }

    ostream & write(ostream & str) const {
      str<<"UMinAlgLS: unconstrained minimization with line search globalization\n";
      str<<"Objective function:\n";
      f.write(str);
      str<<"Solution vector:\n";
      x.write(str);
      str<<"Direction update:\n";
      dc.write(str);
      str<<"Line Search algorithm:\n";
      ls.write(str);
      return str;
    }
  };
}

#endif