InverseKohnSham.h

/*-------------------------------------------------------------------
Copyright 2012 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
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(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
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-------------------------------------------------------------------*/

#ifndef JDFTX_ELECTRONIC_INVERSEKOHNSHAM_H
#define JDFTX_ELECTRONIC_INVERSEKOHNSHAM_H

#include <core/Minimize.h>
#include <core/ScalarFieldArray.h>
#include <electronic/common.h>

class InverseKohnSham : public Minimizable<ScalarFieldArray>
{
public:
        InverseKohnSham(Everything&);
        
        //Interface for minimize:
        void step(const ScalarFieldArray& dir, double alpha);
        double compute(ScalarFieldArray* grad);
        ScalarFieldArray precondition(const ScalarFieldArray& grad);
        void constrain(ScalarFieldArray& dir);
        bool report(int iter);
        double sync(double x) const; 
private:
        Everything& e;
        ScalarFieldArray n; //band structure density (should equal ElecVars::n at end)
        RealKernel gaussCutoff; //gaussian cutoff kernel (of width Control::invertKS_sigma)
        //Chi guess:
        std::shared_ptr<class InvertChi> invertChi; //Compute inverse chi using linear CG
};

#endif // JDFTX_ELECTRONIC_INVERSEKOHNSHAM_H