/* ----------------------------------------------------------------------
   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
   http://lammps.sandia.gov, Sandia National Laboratories
   Steve Plimpton, sjplimp@sandia.gov

   Copyright (2003) Sandia Corporation.  Under the terms of Contract
   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
   certain rights in this software.  This software is distributed under 
   the GNU General Public License.

   See the README file in the top-level LAMMPS directory.
------------------------------------------------------------------------- */

#ifdef PAIR_CLASS

PairStyle(eim,PairEIM)

#else

#ifndef LMP_PAIR_EIM_H
#define LMP_PAIR_EIM_H

#include "stdio.h"
#include "pair.h"

namespace LAMMPS_NS {

class PairEIM : public Pair {
 public:
  PairEIM(class LAMMPS *);
  ~PairEIM();
  void compute(int, int);
  void settings(int, char **);
  void coeff(int, char **);
  void init_style();
  double init_one(int, int);

  int pack_comm(int, int *, double *, int, int *);
  void unpack_comm(int, int, double *);
  int pack_reverse_comm(int, int, double *);
  void unpack_reverse_comm(int, int *, double *);
  double memory_usage();

 private:
  double **cutforcesq,cutmax;
  int nmax;
  double *rho,*fp;
  int rhofp;
  int *map;                   // which element each atom type maps to

  int nelements;              // # of elements to read from potential file
  char **elements;            // element names

  struct Setfl {
    double division,rbig,rsmall;
    int nr;
    int *ielement,*tp;
    double *mass,*negativity,*ra,*ri,*Ec,*q0;
    double *rcutphiA,*rcutphiR,*Eb,*r0,*alpha,*beta,
           *rcutq,*Asigma,*rq,*rcutsigma,*Ac,*zeta,
           *rs;
    double dr,cut;
    double ***Fij,***Gij,***phiij;
    double **cuts;
  };
  Setfl *setfl;

  // potentials as array data

  int nr;
  int nFij,nGij,nphiij;
  double **Fij,**Gij,**phiij;
  int **type2Fij,**type2Gij,**type2phiij;
  
  // potentials in spline form used for force computation

  double dr,rdr;
  double *negativity,*q0;
  double ***Fij_spline,***Gij_spline,***phiij_spline;

  void allocate();
  void array2spline();
  void interpolate(int, double, double *, double **, double);
  int grabglobal(FILE *); 
  int grabsingle(FILE *, int);
  int grabpair(FILE *, int, int);

  double funccutoff(double, double, double);
  double funcphi(int, int, double);
  double funcsigma(int, int, double);
  double funccoul(int, int, double);

  void read_file(char *);
  void deallocate_setfl();
  void file2array();
};

}

#endif
#endif
