#ifndef WANNIER_H_
#define WANNIER_H_

/** \file wannier.h
 * Header file for \ref wannier.c
 * 
 * Contains declarations of functions which reside in \ref wannier.c
 * 
  Project: ParallelCarParrinello
 \author Frederik Heber
 \date 2006

  File: wannier.h
  $Id: wannier.h,v 1.3 2007-10-08 15:43:29 heber Exp $
*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <gsl/gsl_complex.h>

/** Structure contains all variables needed for diagonalization of a matrix with 
 * SerialDiagonalization() or ParallelDiagonalization()
 */
struct DiagonalizationData {
  int Num;        //!< Number of rows/columns
  int AllocNum;   //!< even number of rows/columns
  int NumMatrices;//!< number of matrices to be simultaneously "actively" diagonalized
  int extra;      //!< number of additional matrices that are also, yet "passively" diagonalized (not considered in rotation angle evaluation)
  gsl_matrix *U;   //!< transformation matrix
  gsl_matrix **A;  //!< matrix to be diagonlized
  int *top;       //!< merry-go-round top row of indices
  int *bot;       //!< merry-go-round bottom row of indices
  MPI_Comm *comm; //!< MPI communicator for ParallelDiagonalization()
  int ProcRank;   //!< Rank of this process, used in ParallelDiagonalization()
  int ProcNum;    //!< Number of process in communicator, used in ParallelDiagonalization()
};


void PrintGSLMatrix(struct Problem *P, gsl_matrix *U, int Num, const char *msg);
void ComputeMLWF(struct Problem *P);
void WriteWannierFile(struct Problem *P, double spread, double old_spread, double **WannierCentre, double *WannierSpread);
int ParseWannierFile(struct Problem *P);
void ChangeWannierCentres(struct Problem *P);
void SerialDiagonalization(struct Problem *P, struct DiagonalizationData *DiagData);
void ParallelDiagonalization(struct Problem *P, struct DiagonalizationData *DiagData);
double CalculateSpread(struct Problem *P, int i);
gsl_complex convertComplex (fftw_complex a);
void InitDiagonalization(struct Problem *P, struct DiagonalizationData *DiagData, int Num, int NumMatrices, int extra);
void FreeDiagonalization(struct DiagonalizationData *DiagData);
void OrthogonalizePsis(struct Problem *P);
void StrongOrthogonalizePsis(struct Problem *P);
void Diagonalize(struct Problem *P, struct DiagonalizationData *DiagData);

void CalculateSecondOrderReciprocalMoment(struct Problem *P);

#endif /*WANNIER_H_*/