ElecMinimizer.h

/*-------------------------------------------------------------------
Copyright 2011 Ravishankar Sundararaman

This file is part of JDFTx.

JDFTx is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

JDFTx 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with JDFTx.  If not, see <http://www.gnu.org/licenses/>.
-------------------------------------------------------------------*/

#ifndef JDFTX_ELECTRONIC_ELECMINIMIZER_H
#define JDFTX_ELECTRONIC_ELECMINIMIZER_H

#include <electronic/common.h>
#include <electronic/ColumnBundle.h>
#include <electronic/matrix.h>
#include <core/Minimize.h>

struct ElecGradient
{       std::vector<ColumnBundle> C; 
        std::vector<matrix> Haux;
        const ElecInfo* eInfo;
        
        void init(const Everything& e); 
        
        ElecGradient& operator*=(double alpha); 
};

//Functions required for minimize
void axpy(double alpha, const ElecGradient& x, ElecGradient& y); 
double dot(const ElecGradient& x, const ElecGradient& y, double* auxContrib=0); 
ElecGradient clone(const ElecGradient& x); 
void randomize(ElecGradient& x); 

class ElecMinimizer : public Minimizable<ElecGradient>
{
public:
        ElecMinimizer(Everything& e);
        
        //Virtual functions from Minimizable:
        void step(const ElecGradient& dir, double alpha);
        double compute(ElecGradient* grad, ElecGradient* Kgrad);
        bool report(int iter);
        void constrain(ElecGradient&);
        double sync(double x) const; 
        
private:
        Everything& e;
        ElecVars& eVars;
        ElecInfo& eInfo;
        std::vector<matrix> KgradHaux; 
        std::vector<matrix> rotPrev; 
        std::vector<matrix> rotPrevC; 
        std::vector<matrix> rotPrevCinv; 
        
        bool rotExists; 
        std::shared_ptr<struct SubspaceRotationAdjust> sra; 
};

void bandMinimize(Everything& e); 
void elecMinimize(Everything& e); 
void elecFluidMinimize(Everything& e); 
void convergeEmptyStates(Everything& e); 

#endif // JDFTX_ELECTRONIC_ELECMINIMIZER_H