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energy.h

//
// energy.h
//
// Copyright (C) 1996 Limit Point Systems, Inc.
//
// Author: Curtis Janssen <cljanss@limitpt.com>
// Maintainer: LPS
//
// This file is part of the SC Toolkit.
//
// The SC Toolkit is free software; you can redistribute it and/or modify
// it under the terms of the GNU Library General Public License as published by
// the Free Software Foundation; either version 2, or (at your option)
// any later version.
//
// The SC Toolkit is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public License
// along with the SC Toolkit; see the file COPYING.LIB.  If not, write to
// the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
//
// The U.S. Government is granted a limited license as per AL 91-7.
//

#ifndef _chemistry_molecule_energy_h
#define _chemistry_molecule_energy_h

#ifdef __GNUC__
#pragma interface
#endif

#include <iostream>

#include <math/optimize/function.h>
#include <math/optimize/conv.h>
#include <chemistry/molecule/molecule.h>
#include <chemistry/molecule/coor.h>
#include <chemistry/molecule/hess.h>


class MolecularEnergy: public Function {
  private:
    RefSCDimension moldim_; // the number of cartesian variables
    Ref<MolecularCoor> mc_;
    Ref<Molecule> mol_;
    Ref<MolecularHessian> hess_;
    Ref<MolecularHessian> guesshess_;

    RefSCVector cartesian_gradient_;
    RefSymmSCMatrix cartesian_hessian_;
  protected:
    Ref<PointGroup> initial_pg_;

    void failure(const char *);

    virtual void set_energy(double);

    virtual void set_gradient(RefSCVector&);
    virtual void set_hessian(RefSymmSCMatrix&);

    void x_to_molecule();
    void molecule_to_x();

    int print_molecule_when_changed_;
  public:
    MolecularEnergy(const MolecularEnergy&);
    MolecularEnergy(const Ref<KeyVal>&);
    MolecularEnergy(StateIn&);
    ~MolecularEnergy();

    void save_data_state(StateOut&);

    MolecularEnergy & operator=(const MolecularEnergy&);
    
    virtual double energy();

    virtual Ref<Molecule> molecule() const;
    virtual RefSCDimension moldim() const;
    
    void guess_hessian(RefSymmSCMatrix&);
    RefSymmSCMatrix inverse_hessian(RefSymmSCMatrix&);

    RefSymmSCMatrix hessian();
    int hessian_implemented() const;

    void set_x(const RefSCVector&);

    RefSCVector get_cartesian_x();
    RefSCVector get_cartesian_gradient();
    RefSymmSCMatrix get_cartesian_hessian();

    Ref<MolecularCoor> molecularcoor() { return mc_; }

    virtual void symmetry_changed();

    Ref<NonlinearTransform> change_coordinates();
    
    void print_natom_3(const RefSCVector &,
                       const char *t=0, std::ostream&o=ExEnv::out()) const;
    void print_natom_3(double **, const char *t=0, std::ostream&o=ExEnv::out()) const;
    void print_natom_3(double *, const char *t=0, std::ostream&o=ExEnv::out()) const;

    virtual void print(std::ostream& = ExEnv::out()) const;
};


class SumMolecularEnergy: public MolecularEnergy {
  protected:
    int n_;
    Ref<MolecularEnergy> *mole_;
    double *coef_;
    void compute();
  public:
    SumMolecularEnergy(const Ref<KeyVal> &);
    SumMolecularEnergy(StateIn&);
    ~SumMolecularEnergy();

    void save_data_state(StateOut&);

    int value_implemented() const;
    int gradient_implemented() const;
    int hessian_implemented() const;

    void set_x(const RefSCVector&);
};


/* The MolEnergyConvergence class derives from the Convergence class.  The
MolEnergyConvergence class allows the user to request that cartesian
coordinates be used in evaluating the convergence criteria.  This is
useful, since the internal coordinates can be somewhat arbitary.  If the
optimization is constrained, then the fixed internal coordinates will be
projected out of the cartesian gradients.  The input is similar to that for
Convergence class with the exception that giving none of the convergence
criteria keywords is the same as providing the following input to the
KeyVal constructor:

<pre>
  conv<MolEnergyConvergence>: (
    max_disp = 1.0e-4
    max_grad = 1.0e-4
    graddisp = 1.0e-4
  )
</pre>

For MolEnergyConverence to work, the Function object given to the Optimizer
object must derive from MolecularEnergy.
*/
class MolEnergyConvergence: public Convergence {
  protected:
    Ref<MolecularEnergy> mole_;
    int cartesian_;

    void set_defaults();
  public:
    // Standard constructors and destructor.
    MolEnergyConvergence();
    MolEnergyConvergence(StateIn&);
    MolEnergyConvergence(const Ref<KeyVal>&);
    virtual ~MolEnergyConvergence();

    void save_data_state(StateOut&);

    // Set the current gradient and position information.  These
    //will possibly grab the cartesian infomation if we have a
    //MolecularEnergy.
    void get_grad(const Ref<Function> &);
    void get_x(const Ref<Function> &);
    void set_nextx(const RefSCVector &);

    // Return nonzero if the optimization has converged.
    int converged();
};


#endif

// Local Variables:
// mode: c++
// c-file-style: "CLJ"
// End:

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