// -*- c++ -*- (enables emacs c++ mode)
//===========================================================================
//
// Copyright (C) 2003-2008 Yves Renard
//
// This file is a part of GETFEM++
//
// Getfem++  is  free software;  you  can  redistribute  it  and/or modify it
// under  the  terms  of the  GNU  Lesser General Public License as published
// by  the  Free Software Foundation;  either version 2.1 of the License,  or
// (at your option) any later version.
// This program  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 Lesser General Public
// License for more details.
// You  should  have received a copy of the GNU Lesser General Public License
// along  with  this program;  if not, write to the Free Software Foundation,
// Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
//
// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
//
//===========================================================================

/**@file gmm_inoutput.h
   @author Yves Renard <Yves.Renard@insa-lyon.fr>
   @author Julien Pommier <Julien.Pommier@insa-toulouse.fr>
   @date July 8, 2003.
   @brief Input/output on sparse matrices

   Support Harwell-Boeing and Matrix-Market formats.
*/
#ifndef GMM_INOUTPUT_H
#define GMM_INOUTPUT_H

#include <stdio.h>
#include "gmm_kernel.h"
namespace gmm {

  /*************************************************************************/
  /*                                                                       */
  /*  Functions to read and write Harwell Boeing format.                   */
  /*                                                                       */
  /*************************************************************************/

  // Fri Aug 15 16:29:47 EDT 1997
  // 
  //                      Harwell-Boeing File I/O in C
  //                               V. 1.0
  // 
  //          National Institute of Standards and Technology, MD.
  //                            K.A. Remington
  // ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  //                                NOTICE
  //
  // Permission to use, copy, modify, and distribute this software and
  // its documentation for any purpose and without fee is hereby granted
  // provided that the above copyright notice appear in all copies and
  // that both the copyright notice and this permission notice appear in
  // supporting documentation.
  //
  // Neither the Author nor the Institution (National Institute of Standards
  // and Technology) make any representations about the suitability of this 
  // software for any purpose. This software is provided "as is" without 
  // expressed or implied warranty.
  // ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

  inline void IOHBTerminate(const char *a) { GMM_ASSERT1(false, a);}

  inline bool is_complex_double__(std::complex<double>) { return true; }
  inline bool is_complex_double__(double) { return false; }

  inline int ParseIfmt(const char *fmt, int* perline, int* width) {
    if (SECURE_NONCHAR_SSCANF(fmt, " (%dI%d)", perline, width) != 2) {
      *perline = 1;
      int s = SECURE_NONCHAR_SSCANF(fmt, " (I%d)", width);
      GMM_ASSERT1(s == 1, "invalid HB I-format: " << fmt);
    }
    return *width;
  }
  
  inline int ParseRfmt(const char *fmt, int* perline, int* width,
		       int* prec, int* flag) {
    char p;
    *perline = *width = *flag = *prec = 0;
#ifdef GMM_SECURE_CRT
    if (sscanf_s(fmt, " (%d%c%d.%d)", perline, &p, sizeof(char), width, prec)
	< 3 || !strchr("PEDF", p))
#else
    if (sscanf(fmt, " (%d%c%d.%d)", perline, &p, width, prec) < 3
	|| !strchr("PEDF", p))
#endif
	{
      *perline = 1;
#ifdef GMM_SECURE_CRT
      int s = sscanf_s(fmt, " (%c%d.%d)", &p, sizeof(char), width, prec);
#else
      int s = sscanf(fmt, " (%c%d.%d)", &p, width, prec);
#endif
      GMM_ASSERT1(s>=2 && strchr("PEDF",p), "invalid HB REAL format: " << fmt);
    }
    *flag = p;
    return *width;
  }
      
  /** matrix input/output for Harwell-Boeing format */
  struct HarwellBoeing_IO {
    int nrows() const { return Nrow; }
    int ncols() const { return Ncol; }
    int nnz() const { return Nnzero; }
    int is_complex() const { return Type[0] == 'C'; }
    int is_symmetric() const { return Type[1] == 'S'; }
    int is_hermitian() const { return Type[1] == 'H'; }
    HarwellBoeing_IO() { clear(); }
    HarwellBoeing_IO(const char *filename) { clear(); open(filename); }
    ~HarwellBoeing_IO() { close(); }
    /** open filename and reads header */
    void open(const char *filename);
    /** read the opened file */
    template <typename T, int shift> void read(csc_matrix<T, shift>& A);
    template <typename MAT> void read(MAT &M) IS_DEPRECATED;
    template <typename T, int shift>
    static void write(const char *filename, const csc_matrix<T, shift>& A);
    template <typename T, int shift>
    static void write(const char *filename, const csc_matrix<T, shift>& A,
		      const std::vector<T> &rhs);
    template <typename T, typename INDI, typename INDJ, int shift> 
    static void write(const char *filename,
		      const csc_matrix_ref<T*, INDI*, INDJ*, shift>& A);
    template <typename T, typename INDI, typename INDJ, int shift> 
    static void write(const char *filename,
		      const csc_matrix_ref<T*, INDI*, INDJ*, shift>& A,
		      const std::vector<T> &rhs);

    /** static method for saving the matrix */
    template <typename MAT> static void write(const char *filename,
					      const MAT& A) IS_DEPRECATED;
  private:
    FILE *f;
    char Title[73], Key[9], Rhstype[4], Type[4];
    int Nrow, Ncol, Nnzero, Nrhs;
    char Ptrfmt[17], Indfmt[17], Valfmt[21], Rhsfmt[21];
    int Ptrcrd, Indcrd, Valcrd, Rhscrd; 
    int lcount;


    void close() { if (f) fclose(f); clear(); }
    void clear() { 
      Nrow = Ncol = Nnzero = Nrhs = 0; f = 0; lcount = 0;
      memset(Type, 0, sizeof Type); 
      memset(Key, 0, sizeof Key); 
      memset(Title, 0, sizeof Title); 
    }
    char *getline(char *buf) { 
      if(fgets(buf, BUFSIZ, f) == NULL) return buf; ++lcount;
      int s = SECURE_NONCHAR_SSCANF(buf,"%*s");
      GMM_ASSERT1(s >= 0, "blank line in HB file at line " << lcount);
      return buf;
    }

    int substrtoi(const char *p, size_type len) {
      char s[100]; len = std::min(len, sizeof s - 1);
      SECURE_STRNCPY(s, 100, p, len); s[len] = 0; return atoi(s);
    }
    double substrtod(const char *p, size_type len, int Valflag) {
      char s[100]; len = std::min(len, sizeof s - 1);
      SECURE_STRNCPY(s, 100, p, len); s[len] = 0;
      if ( Valflag != 'F' && !strchr(s,'E')) {
	/* insert a char prefix for exp */
	int last = strlen(s);
	for (int j=last+1;j>=0;j--) {
	  s[j] = s[j-1];
	  if ( s[j] == '+' || s[j] == '-' ) {
	    s[j-1] = Valflag;                    
	    break;
	  }
	}
      }
      return atof(s);
    }
    template <typename IND_TYPE>   
    int readHB_data(IND_TYPE colptr[], IND_TYPE rowind[], 
		    double val[]) {
      /***********************************************************************/
      /*  This function opens and reads the specified file, interpreting its */
      /*  contents as a sparse matrix stored in the Harwell/Boeing standard  */
      /*  format and creating compressed column storage scheme vectors to    */
      /*  hold the index and nonzero value information.                      */
      /*                                                                     */
      /*    ----------                                                       */
      /*    **CAVEAT**                                                       */
      /*    ----------                                                       */
      /*  Parsing real formats from Fortran is tricky, and this file reader  */
      /*  does not claim to be foolproof.   It has been tested for cases     */
      /*  when the real values are printed consistently and evenly spaced on */
      /*  each line, with Fixed (F), and Exponential (E or D) formats.       */
      /*                                                                     */
      /*  **  If the input file does not adhere to the H/B format, the  **   */
      /*  **             results will be unpredictable.                 **   */
      /*                                                                     */
      /***********************************************************************/
      int i,ind,col,offset,count;
      int Ptrperline, Ptrwidth, Indperline, Indwidth;
      int Valperline, Valwidth, Valprec, Nentries;
      int Valflag;           /* Indicates 'E','D', or 'F' float format */
      char line[BUFSIZ];

      /*  Parse the array input formats from Line 3 of HB file  */
      ParseIfmt(Ptrfmt,&Ptrperline,&Ptrwidth);
      ParseIfmt(Indfmt,&Indperline,&Indwidth);
      if ( Type[0] != 'P' ) {          /* Skip if pattern only  */
	ParseRfmt(Valfmt,&Valperline,&Valwidth,&Valprec,&Valflag);
      }

      cout << "Valwidth = " << Valwidth << endl; getchar();
    
      /*  Read column pointer array:   */
      offset = 0;         /* if base 0 storage is declared (via macro def),  */
      /* then storage entries are offset by 1            */
    
      for (count = 0, i=0;i<Ptrcrd;i++) {
	getline(line);
	for (col = 0, ind = 0;ind<Ptrperline;ind++) {
	  if (count > Ncol) break;
	  colptr[count] = substrtoi(line+col,Ptrwidth)-offset;
	  count++; col += Ptrwidth;
	}
      }
    
      /*  Read row index array:  */    
      for (count = 0, i=0;i<Indcrd;i++) {
	getline(line);
	for (col = 0, ind = 0;ind<Indperline;ind++) {
	  if (count == Nnzero) break;
	  rowind[count] = substrtoi(line+col,Indwidth)-offset;
	  count++; col += Indwidth;
	}
      }
    
      /*  Read array of values:  */
      if ( Type[0] != 'P' ) {          /* Skip if pattern only  */
	if ( Type[0] == 'C' ) Nentries = 2*Nnzero;
	else Nentries = Nnzero;
      
	count = 0;
	for (i=0;i<Valcrd;i++) {
	  getline(line);
	  if (Valflag == 'D')  {
            // const_cast Due to aCC excentricity
	    char *p;
	    while( (p = const_cast<char *>(strchr(line,'D')) )) *p = 'E';
	  }
	  for (col = 0, ind = 0;ind<Valperline;ind++) {
	    if (count == Nentries) break;
	    val[count] = substrtod(line+col, Valwidth, Valflag);
	    count++; col += Valwidth;
	  }
	}
      }
      return 1;
    }
  };
  
  inline void HarwellBoeing_IO::open(const char *filename) {
    int Totcrd,Neltvl,Nrhsix;
    char line[BUFSIZ];
    close();
    SECURE_FOPEN(&f, filename, "r");
    GMM_ASSERT1(f, "could not open " << filename);
    /* First line: */
#ifdef GMM_SECURE_CRT
    sscanf_s(getline(line), "%c%s", Title, 72, Key, 8);
#else
    sscanf(getline(line), "%72c%8s", Title, Key);
#endif
    Key[8] = Title[72] = 0;
    /* Second line: */
    Totcrd = Ptrcrd = Indcrd = Valcrd = Rhscrd = 0;
    SECURE_NONCHAR_SSCANF(getline(line), "%d%d%d%d%d", &Totcrd, &Ptrcrd,
			  &Indcrd, &Valcrd, &Rhscrd);
    
    /* Third line: */
    Nrow = Ncol = Nnzero = Neltvl = 0;
#ifdef GMM_SECURE_CRT
    if (sscanf_s(getline(line), "%c%d%d%d%d", Type, 3, &Nrow, &Ncol, &Nnzero,
		 &Neltvl) < 1)
#else
    if (sscanf(getline(line), "%3c%d%d%d%d", Type, &Nrow, &Ncol, &Nnzero,
	       &Neltvl) < 1)
#endif
      IOHBTerminate("Invalid Type info, line 3 of Harwell-Boeing file.\n");
    for (size_type i = 0; i < 3; ++i) Type[i] = toupper(Type[i]);
    
      /*  Fourth line:  */
#ifdef GMM_SECURE_CRT
    if ( sscanf_s(getline(line), "%c%c%c%c",Ptrfmt, 16,Indfmt, 16,Valfmt,
		  20,Rhsfmt, 20) < 3)
#else
    if ( sscanf(getline(line), "%16c%16c%20c%20c",Ptrfmt,Indfmt,Valfmt,
		Rhsfmt) < 3)
#endif
      IOHBTerminate("Invalid format info, line 4 of Harwell-Boeing file.\n"); 
    Ptrfmt[16] = Indfmt[16] = Valfmt[20] = Rhsfmt[20] = 0;
    
    /*  (Optional) Fifth line: */
    if (Rhscrd != 0 ) { 
      Nrhs = Nrhsix = 0;
#ifdef GMM_SECURE_CRT
      if ( sscanf_s(getline(line), "%c%d%d", Rhstype, 3, &Nrhs, &Nrhsix) != 1)
#else
      if ( sscanf(getline(line), "%3c%d%d", Rhstype, &Nrhs, &Nrhsix) != 1)
#endif
	IOHBTerminate("Invalid RHS type information, line 5 of"
		      " Harwell-Boeing file.\n");
    }
  }

  /* only valid for double and complex<double> csc matrices */
  template <typename T, int shift> void
  HarwellBoeing_IO::read(csc_matrix<T, shift>& A) {

    typedef typename csc_matrix<T, shift>::IND_TYPE IND_TYPE;

    GMM_ASSERT1(f, "no file opened!");
    GMM_ASSERT1(Type[0] != 'P',
		"Bad HB matrix format (pattern matrices not supported)");
    GMM_ASSERT1(!is_complex_double__(T()) || Type[0] != 'R',
		"Bad HB matrix format (file contains a REAL matrix)");
    GMM_ASSERT1(is_complex_double__(T()) || Type[0] != 'C',
		"Bad HB matrix format (file contains a COMPLEX matrix)");
    if (A.pr) { delete[] A.pr; delete[] A.ir; delete[] A.jc; }
    A.nc = ncols(); A.nr = nrows();
    A.pr = 0;
    A.jc = new IND_TYPE[ncols()+1];
    A.ir = new IND_TYPE[nnz()];
    A.pr = new T[nnz()];
    readHB_data(A.jc, A.ir, (double*)A.pr);
    for (int i = 0; i <= ncols(); ++i) { A.jc[i] += shift; A.jc[i] -= 1; }
    for (int i = 0; i < nnz(); ++i)    { A.ir[i] += shift; A.ir[i] -= 1; }
  }

  template <typename MAT> void 
  HarwellBoeing_IO::read(MAT &M) {
    csc_matrix<typename gmm::linalg_traits<MAT>::value_type> csc;
    read(csc); 
    resize(M, mat_nrows(csc), mat_ncols(csc));
    copy(csc, M);
  }
  
  template <typename IND_TYPE> 
  inline int writeHB_mat_double(const char* filename, int M, int N, int nz,
				const IND_TYPE colptr[],
				const IND_TYPE rowind[], 
				const double val[], int Nrhs,
				const double rhs[], const double guess[],
				const double exact[], const char* Title,
				const char* Key, const char* Type, 
				const char* Ptrfmt, const char* Indfmt,
				const char* Valfmt, const char* Rhsfmt,
				const char* Rhstype, int shift) {
    /************************************************************************/
    /*  The writeHB function opens the named file and writes the specified  */
    /*  matrix and optional right-hand-side(s) to that file in              */
    /*  Harwell-Boeing format.                                              */
    /*                                                                      */
    /*  For a description of the Harwell Boeing standard, see:              */
    /*            Duff, et al.,  ACM TOMS Vol.15, No.1, March 1989          */
    /*                                                                      */
    /************************************************************************/
    FILE *out_file;
    int i, entry, offset, j, acount, linemod;
    int totcrd, ptrcrd, indcrd, valcrd, rhscrd;
    int nvalentries, nrhsentries;
    int Ptrperline, Ptrwidth, Indperline, Indwidth;
    int Rhsperline, Rhswidth, Rhsprec, Rhsflag;
    int Valperline, Valwidth, Valprec;
    int Valflag;           /* Indicates 'E','D', or 'F' float format */
    char pformat[16],iformat[16],vformat[19],rformat[19];
    
    if ( Type[0] == 'C' )
      { nvalentries = 2*nz; nrhsentries = 2*M; }
    else
      { nvalentries = nz; nrhsentries = M; }
    
    if ( filename != NULL ) {
      SECURE_FOPEN(&out_file, filename, "w");
      GMM_ASSERT1(out_file != NULL, "Error: Cannot open file: " << filename);
    } else out_file = stdout;
    
    if ( Ptrfmt == NULL ) Ptrfmt = "(8I10)";
    ParseIfmt(Ptrfmt, &Ptrperline, &Ptrwidth);
    SECURE_SPRINTF1(pformat,sizeof(pformat),"%%%dd",Ptrwidth);
    ptrcrd = (N+1)/Ptrperline;
    if ( (N+1)%Ptrperline != 0) ptrcrd++;
    
    if ( Indfmt == NULL ) Indfmt =  Ptrfmt;
    ParseIfmt(Indfmt, &Indperline, &Indwidth);
    SECURE_SPRINTF1(iformat,sizeof(iformat), "%%%dd",Indwidth);
    indcrd = nz/Indperline;
    if ( nz%Indperline != 0) indcrd++;
    
    if ( Type[0] != 'P' ) {          /* Skip if pattern only  */
      if ( Valfmt == NULL ) Valfmt = "(4E21.13)";
      ParseRfmt(Valfmt, &Valperline, &Valwidth, &Valprec, &Valflag);
      if (Valflag == 'D') *strchr(Valfmt,'D') = 'E';
      if (Valflag == 'F')
	SECURE_SPRINTF2(vformat, sizeof(vformat), "%% %d.%df", Valwidth,
			Valprec);
      else
	SECURE_SPRINTF2(vformat, sizeof(vformat), "%% %d.%dE", Valwidth,
			Valprec);
      valcrd = nvalentries/Valperline;
      if ( nvalentries%Valperline != 0) valcrd++;
    } else valcrd = 0;
    
    if ( Nrhs > 0 ) {
      if ( Rhsfmt == NULL ) Rhsfmt = Valfmt;
      ParseRfmt(Rhsfmt,&Rhsperline,&Rhswidth,&Rhsprec, &Rhsflag);
      if (Rhsflag == 'F')
	SECURE_SPRINTF2(rformat,sizeof(rformat), "%% %d.%df",Rhswidth,Rhsprec);
      else
	SECURE_SPRINTF2(rformat,sizeof(rformat), "%% %d.%dE",Rhswidth,Rhsprec);
      if (Rhsflag == 'D') *strchr(Rhsfmt,'D') = 'E';
      rhscrd = nrhsentries/Rhsperline; 
      if ( nrhsentries%Rhsperline != 0) rhscrd++;
      if ( Rhstype[1] == 'G' ) rhscrd+=rhscrd;
      if ( Rhstype[2] == 'X' ) rhscrd+=rhscrd;
      rhscrd*=Nrhs;
    } else rhscrd = 0;
    
    totcrd = 4+ptrcrd+indcrd+valcrd+rhscrd;
    
    
    /*  Print header information:  */
    
    fprintf(out_file,"%-72s%-8s\n%14d%14d%14d%14d%14d\n",Title, Key, totcrd,
	    ptrcrd, indcrd, valcrd, rhscrd);
    fprintf(out_file,"%3s%11s%14d%14d%14d%14d\n",Type,"          ", M, N, nz, 0);
    fprintf(out_file,"%-16s%-16s%-20s", Ptrfmt, Indfmt, Valfmt);
    if ( Nrhs != 0 ) {
      /* Print Rhsfmt on fourth line and                              */
      /*  optional fifth header line for auxillary vector information:*/
      fprintf(out_file,"%-20s\n%-14s%d\n",Rhsfmt,Rhstype,Nrhs);
    }
    else
      fprintf(out_file,"\n");
    
    offset = 1 - shift;  /* if base 0 storage is declared (via macro def), */
    /* then storage entries are offset by 1           */
    
    /*  Print column pointers:   */
    for (i = 0; i < N+1; i++) {
      entry = colptr[i]+offset;
      fprintf(out_file,pformat,entry);
      if ( (i+1)%Ptrperline == 0 ) fprintf(out_file,"\n");
    }
    
    if ( (N+1) % Ptrperline != 0 ) fprintf(out_file,"\n");
    
    /*  Print row indices:       */
    for (i=0;i<nz;i++) {
      entry = rowind[i]+offset;
      fprintf(out_file,iformat,entry);
      if ( (i+1)%Indperline == 0 ) fprintf(out_file,"\n");
    }
    
    if ( nz % Indperline != 0 ) fprintf(out_file,"\n");
    
    /*  Print values:            */
    
    if ( Type[0] != 'P' ) {          /* Skip if pattern only  */
      for (i=0;i<nvalentries;i++) {
	fprintf(out_file,vformat,val[i]);
	if ( (i+1)%Valperline == 0 ) fprintf(out_file,"\n");
      }
      
      if ( nvalentries % Valperline != 0 ) fprintf(out_file,"\n");
      
      /*  Print right hand sides:  */
      acount = 1;
      linemod=0;
      if ( Nrhs > 0 ) {
	for (j=0;j<Nrhs;j++) {
	  for (i=0;i<nrhsentries;i++) {
	    fprintf(out_file,rformat,rhs[i] /* *Rhswidth */);
	    if ( acount++%Rhsperline == linemod ) fprintf(out_file,"\n");
	  }
	  if ( acount%Rhsperline != linemod ) {
	    fprintf(out_file,"\n");
	    linemod = (acount-1)%Rhsperline;
	  }
	  if ( Rhstype[1] == 'G' ) {
	    for (i=0;i<nrhsentries;i++) {
	      fprintf(out_file,rformat,guess[i] /* *Rhswidth */);
	      if ( acount++%Rhsperline == linemod ) fprintf(out_file,"\n");
	    }
	    if ( acount%Rhsperline != linemod ) {
	      fprintf(out_file,"\n");
	      linemod = (acount-1)%Rhsperline;
	    }
	  }
	  if ( Rhstype[2] == 'X' ) {
	    for (i=0;i<nrhsentries;i++) {
	      fprintf(out_file,rformat,exact[i] /* *Rhswidth */);
	      if ( acount++%Rhsperline == linemod ) fprintf(out_file,"\n");
	    }
	    if ( acount%Rhsperline != linemod ) {
	      fprintf(out_file,"\n");
	      linemod = (acount-1)%Rhsperline;
	    }
	  }
	}
      }
    }
    int s = fclose(out_file);
    GMM_ASSERT1(s == 0, "Error closing file in writeHB_mat_double().");
    return 1;
  }
  
  template <typename T, int shift> void
  HarwellBoeing_IO::write(const char *filename,
			  const csc_matrix<T, shift>& A) {
    write(filename, csc_matrix_ref<T*, unsigned*, unsigned *, shift>
	  (A.pr, A.ir, A.jc, A.nr, A.nc));
  }

  template <typename T, int shift> void
  HarwellBoeing_IO::write(const char *filename,
			  const csc_matrix<T, shift>& A,
			  const std::vector<T> &rhs) {
    write(filename, csc_matrix_ref<T*, unsigned*, unsigned *, shift>
	  (A.pr, A.ir, A.jc, A.nr, A.nc), rhs);
  }

  template <typename T, typename INDI, typename INDJ, int shift> void
  HarwellBoeing_IO::write(const char *filename,
			  const csc_matrix_ref<T*, INDI*, INDJ*, shift>& A) {
    const char *t = 0;    
    if (is_complex_double__(T()))
      if (mat_nrows(A) == mat_ncols(A)) t = "CUA"; else t = "CRA";
    else
      if (mat_nrows(A) == mat_ncols(A)) t = "RUA"; else t = "RRA";
    writeHB_mat_double(filename, mat_nrows(A), mat_ncols(A),
		       A.jc[mat_ncols(A)], A.jc, A.ir,
		       (const double *)A.pr,
		       0, 0, 0, 0, "GETFEM++ CSC MATRIX", "CSCMAT",
		       t, 0, 0, 0, 0, "F", shift);
  }

  template <typename T, typename INDI, typename INDJ, int shift> void
  HarwellBoeing_IO::write(const char *filename,
			  const csc_matrix_ref<T*, INDI*, INDJ*, shift>& A,
			  const std::vector<T> &rhs) {
    const char *t = 0;
    if (is_complex_double__(T()))
      if (mat_nrows(A) == mat_ncols(A)) t = "CUA"; else t = "CRA";
    else
      if (mat_nrows(A) == mat_ncols(A)) t = "RUA"; else t = "RRA";
    int Nrhs = gmm::vect_size(rhs) / mat_nrows(A);
    writeHB_mat_double(filename, mat_nrows(A), mat_ncols(A),
		       A.jc[mat_ncols(A)], A.jc, A.ir,
		       (const double *)A.pr,
		       Nrhs, (const double *)(&rhs[0]), 0, 0,
		       "GETFEM++ CSC MATRIX", "CSCMAT",
		       t, 0, 0, 0, 0, "F  ", shift);
  }

  
  template <typename MAT> void
  HarwellBoeing_IO::write(const char *filename, const MAT& A) {
    gmm::csc_matrix<typename gmm::linalg_traits<MAT>::value_type> 
      tmp(gmm::mat_nrows(A), gmm::mat_ncols(A));
    gmm::copy(A,tmp); 
    HarwellBoeing_IO::write(filename, tmp);
  }

  /** save a "double" or "std::complex<double>" csc matrix into a
      HarwellBoeing file
  */
  template <typename T, int shift> inline void
  Harwell_Boeing_save(const std::string &filename,
		      const csc_matrix<T, shift>& A)
  { HarwellBoeing_IO::write(filename.c_str(), A); }

  /** save a reference on "double" or "std::complex<double>" csc matrix
      into a HarwellBoeing file
  */
  template <typename T, typename INDI, typename INDJ, int shift> inline void
  Harwell_Boeing_save(const std::string &filename,
		      const csc_matrix_ref<T, INDI, INDJ, shift>& A)
  { HarwellBoeing_IO::write(filename.c_str(), A); }

  /** save a "double" or "std::complex<double>" generic matrix
      into a HarwellBoeing file making a copy in a csc matrix
  */
  template <typename MAT> inline void
  Harwell_Boeing_save(const std::string &filename, const MAT& A) {
    gmm::csc_matrix<typename gmm::linalg_traits<MAT>::value_type> 
      tmp(gmm::mat_nrows(A), gmm::mat_ncols(A));
    gmm::copy(A, tmp); 
    HarwellBoeing_IO::write(filename.c_str(), tmp);
  }

  template <typename MAT, typename VECT> inline void
  Harwell_Boeing_save(const std::string &filename, const MAT& A,
		      const VECT &RHS) {
    typedef typename gmm::linalg_traits<MAT>::value_type T;
    gmm::csc_matrix<T> tmp(gmm::mat_nrows(A), gmm::mat_ncols(A));
    gmm::copy(A, tmp);
    std::vector<T> tmprhs(gmm::vect_size(RHS));
    gmm::copy(RHS, tmprhs);
    HarwellBoeing_IO::write(filename.c_str(), tmp, tmprhs);
  }

  /** load a "double" or "std::complex<double>" csc matrix from a
      HarwellBoeing file
  */
  template <typename T, int shift> void
  Harwell_Boeing_load(const std::string &filename, csc_matrix<T, shift>& A) {
    HarwellBoeing_IO h(filename.c_str()); h.read(A);
  }

  /** load a "double" or "std::complex<double>" generic matrix from a
      HarwellBoeing file
  */
  template <typename MAT> void
  Harwell_Boeing_load(const std::string &filename, MAT& A) {
    csc_matrix<typename gmm::linalg_traits<MAT>::value_type> csc;
    Harwell_Boeing_load(filename, csc);
    resize(A, mat_nrows(csc), mat_ncols(csc));
    copy(csc, A);
  }

  /*************************************************************************/
  /*                                                                       */
  /*  Functions to read and write MatrixMarket format.                     */
  /*                                                                       */
  /*************************************************************************/

  /* 
   *   Matrix Market I/O library for ANSI C
   *
   *   See http://math.nist.gov/MatrixMarket for details.
   *
   *
   */

#define MM_MAX_LINE_LENGTH 1025
#define MatrixMarketBanner "%%MatrixMarket"
#define MM_MAX_TOKEN_LENGTH 64

  typedef char MM_typecode[4];

  /******************* MM_typecode query functions *************************/

#define mm_is_matrix(typecode)	        ((typecode)[0]=='M')
  
#define mm_is_sparse(typecode)	        ((typecode)[1]=='C')
#define mm_is_coordinate(typecode)      ((typecode)[1]=='C')
#define mm_is_dense(typecode)	        ((typecode)[1]=='A')
#define mm_is_array(typecode)	        ((typecode)[1]=='A')
  
#define mm_is_complex(typecode)	        ((typecode)[2]=='C')
#define mm_is_real(typecode)	        ((typecode)[2]=='R')
#define mm_is_pattern(typecode)	        ((typecode)[2]=='P')
#define mm_is_integer(typecode)         ((typecode)[2]=='I')
  
#define mm_is_symmetric(typecode)       ((typecode)[3]=='S')
#define mm_is_general(typecode)	        ((typecode)[3]=='G')
#define mm_is_skew(typecode)	        ((typecode)[3]=='K')
#define mm_is_hermitian(typecode)       ((typecode)[3]=='H')
  
  /******************* MM_typecode modify fucntions ************************/

#define mm_set_matrix(typecode)	        ((*typecode)[0]='M')
#define mm_set_coordinate(typecode)	((*typecode)[1]='C')
#define mm_set_array(typecode)	        ((*typecode)[1]='A')
#define mm_set_dense(typecode)	        mm_set_array(typecode)
#define mm_set_sparse(typecode)	        mm_set_coordinate(typecode)

#define mm_set_complex(typecode)        ((*typecode)[2]='C')
#define mm_set_real(typecode)	        ((*typecode)[2]='R')
#define mm_set_pattern(typecode)        ((*typecode)[2]='P')
#define mm_set_integer(typecode)        ((*typecode)[2]='I')


#define mm_set_symmetric(typecode)      ((*typecode)[3]='S')
#define mm_set_general(typecode)        ((*typecode)[3]='G')
#define mm_set_skew(typecode)	        ((*typecode)[3]='K')
#define mm_set_hermitian(typecode)      ((*typecode)[3]='H')

#define mm_clear_typecode(typecode)     ((*typecode)[0]=(*typecode)[1]= \
			       	        (*typecode)[2]=' ',(*typecode)[3]='G')

#define mm_initialize_typecode(typecode) mm_clear_typecode(typecode)


  /******************* Matrix Market error codes ***************************/


#define MM_COULD_NOT_READ_FILE	11
#define MM_PREMATURE_EOF		12
#define MM_NOT_MTX				13
#define MM_NO_HEADER			14
#define MM_UNSUPPORTED_TYPE		15
#define MM_LINE_TOO_LONG		16
#define MM_COULD_NOT_WRITE_FILE	17


  /******************** Matrix Market internal definitions *****************

   MM_matrix_typecode: 4-character sequence

	                object 	    sparse/   	data        storage 
	                            dense     	type        scheme

   string position:	 [0]        [1]		[2]         [3]

   Matrix typecode:     M(atrix)    C(oord)	R(eal)      G(eneral)
		                    A(array)    C(omplex)   H(ermitian)
	                                        P(attern)   S(ymmetric)
                                                I(nteger)   K(kew)

  ***********************************************************************/

#define MM_MTX_STR	   "matrix"
#define MM_ARRAY_STR	   "array"
#define MM_DENSE_STR	   "array"
#define MM_COORDINATE_STR  "coordinate" 
#define MM_SPARSE_STR	   "coordinate"
#define MM_COMPLEX_STR	   "complex"
#define MM_REAL_STR	   "real"
#define MM_INT_STR	   "integer"
#define MM_GENERAL_STR     "general"
#define MM_SYMM_STR	   "symmetric"
#define MM_HERM_STR	   "hermitian"
#define MM_SKEW_STR	   "skew-symmetric"
#define MM_PATTERN_STR     "pattern"

  inline char  *mm_typecode_to_str(MM_typecode matcode) {
    char buffer[MM_MAX_LINE_LENGTH];
    const char *types[4] = {0,0,0,0};
    /*    int error =0; */
    /*   int i; */
    
    /* check for MTX type */
    if (mm_is_matrix(matcode)) 
      types[0] = MM_MTX_STR;
    /*
      else
      error=1;
    */
    /* check for CRD or ARR matrix */
    if (mm_is_sparse(matcode))
      types[1] = MM_SPARSE_STR;
    else
      if (mm_is_dense(matcode))
        types[1] = MM_DENSE_STR;
      else
        return NULL;
    
    /* check for element data type */
    if (mm_is_real(matcode))
      types[2] = MM_REAL_STR;
    else
      if (mm_is_complex(matcode))
        types[2] = MM_COMPLEX_STR;
      else
	if (mm_is_pattern(matcode))
	  types[2] = MM_PATTERN_STR;
	else
	  if (mm_is_integer(matcode))
	    types[2] = MM_INT_STR;
	  else
	    return NULL;
    
    
    /* check for symmetry type */
    if (mm_is_general(matcode))
      types[3] = MM_GENERAL_STR;
    else if (mm_is_symmetric(matcode))
      types[3] = MM_SYMM_STR;
    else if (mm_is_hermitian(matcode))
      types[3] = MM_HERM_STR;
    else  if (mm_is_skew(matcode))
      types[3] = MM_SKEW_STR;
    else
      return NULL;
    
    SECURE_SPRINTF4(buffer, sizeof(buffer), "%s %s %s %s", types[0], types[1],
		    types[2], types[3]);
    return SECURE_STRDUP(buffer);
    
  }
  
  inline int mm_read_banner(FILE *f, MM_typecode *matcode) {
    char line[MM_MAX_LINE_LENGTH];
    char banner[MM_MAX_TOKEN_LENGTH];
    char mtx[MM_MAX_TOKEN_LENGTH]; 
    char crd[MM_MAX_TOKEN_LENGTH];
    char data_type[MM_MAX_TOKEN_LENGTH];
    char storage_scheme[MM_MAX_TOKEN_LENGTH];
    char *p;
    /*    int ret_code; */
    
    mm_clear_typecode(matcode);  
    
    if (fgets(line, MM_MAX_LINE_LENGTH, f) == NULL) 
      return MM_PREMATURE_EOF;

#ifdef GMM_SECURE_CRT
    if (sscanf_s(line, "%s %s %s %s %s", banner, sizeof(banner),
		 mtx, sizeof(mtx), crd, sizeof(crd), data_type,
		 sizeof(data_type), storage_scheme,
		 sizeof(storage_scheme)) != 5)
#else
	if (sscanf(line, "%s %s %s %s %s", banner, mtx, crd,
		   data_type, storage_scheme) != 5)
#endif
      return MM_PREMATURE_EOF;

    for (p=mtx; *p!='\0'; *p=tolower(*p),p++);  /* convert to lower case */
    for (p=crd; *p!='\0'; *p=tolower(*p),p++);  
    for (p=data_type; *p!='\0'; *p=tolower(*p),p++);
    for (p=storage_scheme; *p!='\0'; *p=tolower(*p),p++);

    /* check for banner */
    if (strncmp(banner, MatrixMarketBanner, strlen(MatrixMarketBanner)) != 0)
      return MM_NO_HEADER;

    /* first field should be "mtx" */
    if (strcmp(mtx, MM_MTX_STR) != 0)
      return  MM_UNSUPPORTED_TYPE;
    mm_set_matrix(matcode);


    /* second field describes whether this is a sparse matrix (in coordinate
       storgae) or a dense array */


    if (strcmp(crd, MM_SPARSE_STR) == 0)
      mm_set_sparse(matcode);
    else
      if (strcmp(crd, MM_DENSE_STR) == 0)
	mm_set_dense(matcode);
      else
        return MM_UNSUPPORTED_TYPE;
    

    /* third field */

    if (strcmp(data_type, MM_REAL_STR) == 0)
      mm_set_real(matcode);
    else
      if (strcmp(data_type, MM_COMPLEX_STR) == 0)
        mm_set_complex(matcode);
      else
	if (strcmp(data_type, MM_PATTERN_STR) == 0)
	  mm_set_pattern(matcode);
	else
	  if (strcmp(data_type, MM_INT_STR) == 0)
	    mm_set_integer(matcode);
	  else
	    return MM_UNSUPPORTED_TYPE;
    

    /* fourth field */

    if (strcmp(storage_scheme, MM_GENERAL_STR) == 0)
      mm_set_general(matcode);
    else
      if (strcmp(storage_scheme, MM_SYMM_STR) == 0)
        mm_set_symmetric(matcode);
      else
	if (strcmp(storage_scheme, MM_HERM_STR) == 0)
	  mm_set_hermitian(matcode);
	else
	  if (strcmp(storage_scheme, MM_SKEW_STR) == 0)
	    mm_set_skew(matcode);
	  else
	    return MM_UNSUPPORTED_TYPE;
        
    return 0;
  }

  inline int mm_read_mtx_crd_size(FILE *f, int *M, int *N, int *nz ) {
    char line[MM_MAX_LINE_LENGTH];
    /* int ret_code;*/
    int num_items_read;
    
    /* set return null parameter values, in case we exit with errors */
    *M = *N = *nz = 0;
    
    /* now continue scanning until you reach the end-of-comments */
    do {
      if (fgets(line,MM_MAX_LINE_LENGTH,f) == NULL) 
	return MM_PREMATURE_EOF;
    } while (line[0] == '%');
    
    /* line[] is either blank or has M,N, nz */
    if (SECURE_NONCHAR_SSCANF(line, "%d %d %d", M, N, nz) == 3) return 0;
    else
      do { 
	num_items_read = SECURE_NONCHAR_FSCANF(f, "%d %d %d", M, N, nz); 
	if (num_items_read == EOF) return MM_PREMATURE_EOF;
      }
      while (num_items_read != 3);
    
    return 0;
  }


  inline int mm_read_mtx_crd_data(FILE *f, int, int, int nz, int I[],
				  int J[], double val[], MM_typecode matcode) {
    int i;
    if (mm_is_complex(matcode)) {
      for (i=0; i<nz; i++)
	if (SECURE_NONCHAR_FSCANF(f, "%d %d %lg %lg", &I[i], &J[i],
				  &val[2*i], &val[2*i+1])
	    != 4) return MM_PREMATURE_EOF;
    }
    else if (mm_is_real(matcode)) {
      for (i=0; i<nz; i++) {
	if (SECURE_NONCHAR_FSCANF(f, "%d %d %lg\n", &I[i], &J[i], &val[i])
	    != 3) return MM_PREMATURE_EOF;
	
      }
    }
    else if (mm_is_pattern(matcode)) {
      for (i=0; i<nz; i++)
	if (SECURE_NONCHAR_FSCANF(f, "%d %d", &I[i], &J[i])
	    != 2) return MM_PREMATURE_EOF;
    }
    else return MM_UNSUPPORTED_TYPE;

    return 0;
  }

  inline int mm_write_mtx_crd(const char *fname, int M, int N, int nz,
			      int I[], int J[], const double val[],
			      MM_typecode matcode) {
    FILE *f;
    int i;
    
    if (strcmp(fname, "stdout") == 0) 
      f = stdout;
    else {
      SECURE_FOPEN(&f, fname, "w");
      if (f == NULL)
        return MM_COULD_NOT_WRITE_FILE;
    }
    
    /* print banner followed by typecode */
    fprintf(f, "%s ", MatrixMarketBanner);
    char *str = mm_typecode_to_str(matcode);
    fprintf(f, "%s\n", str);
    free(str);
    
    /* print matrix sizes and nonzeros */
    fprintf(f, "%d %d %d\n", M, N, nz);
    
    /* print values */
    if (mm_is_pattern(matcode))
      for (i=0; i<nz; i++)
	fprintf(f, "%d %d\n", I[i], J[i]);
    else
      if (mm_is_real(matcode))
        for (i=0; i<nz; i++)
	  fprintf(f, "%d %d %20.16g\n", I[i], J[i], val[i]);
      else
	if (mm_is_complex(matcode))
	  for (i=0; i<nz; i++)
            fprintf(f, "%d %d %20.16g %20.16g\n", I[i], J[i], val[2*i], 
		    val[2*i+1]);
	else {
	  if (f != stdout) fclose(f);
	  return MM_UNSUPPORTED_TYPE;
	}
    
    if (f !=stdout) fclose(f); 
    return 0;
  }
  

  /** matrix input/output for MatrixMarket storage */
  class MatrixMarket_IO {
    FILE *f;
    bool isComplex, isSymmetric, isHermitian;
    int row, col, nz;
    MM_typecode matcode;
  public:
    MatrixMarket_IO() : f(0) {}
    MatrixMarket_IO(const char *filename) : f(0) { open(filename); }
    ~MatrixMarket_IO() { if (f) fclose(f); f = 0; }

    int nrows() const { return row; }
    int ncols() const { return col; }
    int nnz() const { return nz; }
    int is_complex() const { return isComplex; }
    int is_symmetric() const { return isSymmetric; }
    int is_hermitian() const { return isHermitian; }

    /* open filename and reads header */
    void open(const char *filename);
    /* read opened file */
    template <typename Matrix> void read(Matrix &A);
    /* write a matrix */
    template <typename T, int shift> static void 
    write(const char *filename, const csc_matrix<T, shift>& A);  
    template <typename T, typename INDI, typename INDJ, int shift> static void 
    write(const char *filename,
	  const csc_matrix_ref<T*, INDI*, INDJ*, shift>& A);  
    template <typename MAT> static void 
    write(const char *filename, const MAT& A);  
  };

  /** load a matrix-market file */
  template <typename Matrix> inline void
  MatrixMarket_load(const char *filename, Matrix& A) {
    MatrixMarket_IO mm; mm.open(filename);
    mm.read(A);
  }
  /** write a matrix-market file */
  template <typename T, int shift> void
  MatrixMarket_save(const char *filename, const csc_matrix<T, shift>& A) {
    MatrixMarket_IO mm; mm.write(filename, A);
  }

  template <typename T, typename INDI, typename INDJ, int shift> inline void
  MatrixMarket_save(const char *filename,
		    const csc_matrix_ref<T, INDI, INDJ, shift>& A) {
    MatrixMarket_IO mm; mm.write(filename, A);
  }


  inline void MatrixMarket_IO::open(const char *filename) {
    if (f) { fclose(f); }
    SECURE_FOPEN(&f, filename, "r");
    GMM_ASSERT1(f, "Sorry, cannot open file " << filename);
    int s1 = mm_read_banner(f, &matcode);
    GMM_ASSERT1(s1 == 0, "Sorry, cannnot find the matrix market banner in "
		<< filename);
    int s2 = mm_is_coordinate(matcode), s3 = mm_is_matrix(matcode);
    GMM_ASSERT1(s2 > 0 && s3 > 0,
		"file is not coordinate storage or is not a matrix");
    int s4 = mm_is_pattern(matcode);
    GMM_ASSERT1(s4 == 0,
	       "the file does only contain the pattern of a sparse matrix");
    int s5 = mm_is_skew(matcode);
    GMM_ASSERT1(s5 == 0, "not currently supporting skew symmetric");
    isSymmetric = mm_is_symmetric(matcode) || mm_is_hermitian(matcode); 
    isHermitian = mm_is_hermitian(matcode); 
    isComplex =   mm_is_complex(matcode);
    mm_read_mtx_crd_size(f, &row, &col, &nz);
  }

  template <typename Matrix> void MatrixMarket_IO::read(Matrix &A) {
    typedef typename linalg_traits<Matrix>::value_type T;
    GMM_ASSERT1(f, "no file opened!");
    GMM_ASSERT1(!is_complex_double__(T()) || isComplex,
		"Bad MM matrix format (complex matrix expected)");
    GMM_ASSERT1(is_complex_double__(T()) || !isComplex,
		"Bad MM matrix format (real matrix expected)");
    A = Matrix(row, col);
    gmm::clear(A);
    
    std::vector<int> I(nz), J(nz);
    std::vector<typename Matrix::value_type> PR(nz);
    mm_read_mtx_crd_data(f, row, col, nz, &I[0], &J[0],
			 (double*)&PR[0], matcode);
    
    for (size_type i = 0; i < size_type(nz); ++i) A(I[i]-1, J[i]-1) = PR[i];
  }

  template <typename T, int shift> void 
  MatrixMarket_IO::write(const char *filename, const csc_matrix<T, shift>& A) {
    write(filename, csc_matrix_ref<T*,unsigned*,unsigned*,shift>
	  (A.pr, A.ir, A.jc, A.nr, A.nc));
  }

  template <typename T, typename INDI, typename INDJ, int shift> void 
  MatrixMarket_IO::write(const char *filename, 
			 const csc_matrix_ref<T*, INDI*, INDJ*, shift>& A) {
    static MM_typecode t1 = {'M', 'C', 'R', 'G'};
    static MM_typecode t2 = {'M', 'C', 'C', 'G'};
    MM_typecode t;
    
    if (is_complex_double__(T())) std::copy(&(t2[0]), &(t2[0])+4, &(t[0]));
    else std::copy(&(t1[0]), &(t1[0])+4, &(t[0]));
    size_type nz = A.jc[mat_ncols(A)];
    std::vector<int> I(nz), J(nz);
    for (size_type j=0; j < mat_ncols(A); ++j) {      
      for (size_type i = A.jc[j]; i < A.jc[j+1]; ++i) {
	I[i] = A.ir[i] + 1 - shift;
	J[i] = j + 1;
      }
    }
    mm_write_mtx_crd(filename, mat_nrows(A), mat_ncols(A),
		     nz, &I[0], &J[0], (const double *)A.pr, t);
  }


  template <typename MAT> void
  MatrixMarket_IO::write(const char *filename, const MAT& A) {
    gmm::csc_matrix<typename gmm::linalg_traits<MAT>::value_type> 
      tmp(gmm::mat_nrows(A), gmm::mat_ncols(A));
    gmm::copy(A,tmp); 
    MatrixMarket_IO::write(filename, tmp);
  }

  template<typename VEC> static void vecsave(std::string fname, const VEC& V) {
    std::ofstream f(fname.c_str()); f.precision(16);
    for (size_type i=0; i < gmm::vect_size(V); ++i) f << V[i] << "\n"; 
  } 

  template<typename VEC> static void vecload(std::string fname,
					     const VEC& V_) {
    VEC &V(const_cast<VEC&>(V_));
    std::ifstream f(fname.c_str());
    for (size_type i=0; i < gmm::vect_size(V); ++i) f >> V[i]; 
  }
}


#endif //  GMM_INOUTPUT_H
