fcscmat.h

/*
This file is distributed as part of the BIAS library (Basic ImageAlgorithmS)
but it has not been developed by the authors of BIAS.

For copyright, author and license information see below.
*/


/*
*
* Template Numerical Toolkit (TNT): Linear Algebra Module
*
* Mathematical and Computational Sciences Division
* National Institute of Technology,
* Gaithersburg, MD USA
*
*
* This software was developed at the National Institute of Standards and
* Technology (NIST) by employees of the Federal Government in the course
* of their official duties. Pursuant to title 17 Section 105 of the
* United States Code, this software is not subject to copyright protection
* and is in the public domain.  The Template Numerical Toolkit (TNT) is
* an experimental system.  NIST assumes no responsibility whatsoever for
* its use by other parties, and makes no guarantees, expressed or implied,
* about its quality, reliability, or any other characteristic.
*
* BETA VERSION INCOMPLETE AND SUBJECT TO CHANGE
* see http://math.nist.gov/tnt for latest updates.
*
*/



//  Templated compressed sparse column matrix (Fortran conventions).
//  uses 1-based offsets in storing row indices.
//  Used primarily to interface with Fortran sparse matrix libaries.
//  (CANNOT BE USED AS AN STL CONTAINER.)


#ifndef FCSCMAT_H
#define FCSCMAT_H

#include <iostream>
#include <cassert>
#include "tnt.h"
#include "vec.h"



namespace TNT
{
  template <class T>
  class Fortran_Sparse_Col_Matrix 
  {

  protected:

    Vector<T>           val_;       // data values (nz_ elements)
    Vector<Subscript>   rowind_;    // row_ind (nz_ elements)
    Vector<Subscript>   colptr_;    // col_ptr (n_+1 elements)

    int nz_;                   // number of nonzeros
    Subscript m_;              // global dimensions
    Subscript n_;

  public:


    Fortran_Sparse_Col_Matrix(void);
    Fortran_Sparse_Col_Matrix(const Fortran_Sparse_Col_Matrix<T> &S)
      : val_(S.val_), rowind_(S.rowind_), colptr_(S.colptr_), nz_(S.nz_),
      m_(S.m_), n_(S.n_) {};
    Fortran_Sparse_Col_Matrix(Subscript M, Subscript N, 
      Subscript nz, const T  *val,  const Subscript *r, 
      const Subscript *c) : val_(nz, val), rowind_(nz, r), 
      colptr_(N+1, c), nz_(nz), m_(M), n_(N) {};

    Fortran_Sparse_Col_Matrix(Subscript M, Subscript N, 
      Subscript nz, char *val,  char  *r, 
      char *c) : val_(nz, val), rowind_(nz, r), 
      colptr_(N+1, c), nz_(nz), m_(M), n_(N) {};

    Fortran_Sparse_Col_Matrix(Subscript M, Subscript N, 
      Subscript nz, const T  *val, Subscript *r, Subscript *c)
      : val_(nz, val), rowind_(nz, r), colptr_(N+1, c), nz_(nz), 
      m_(M), n_(N) {};

    ~Fortran_Sparse_Col_Matrix() {};


    T &      val(Subscript i) { return val_(i); }
    const T &      val(Subscript i) const { return val_(i); }

    Subscript &   row_ind(Subscript i) { return rowind_(i); }
    const Subscript &   row_ind(Subscript i) const { return rowind_(i); }

    Subscript    col_ptr(Subscript i) { return colptr_(i);}
    const Subscript    col_ptr(Subscript i) const { return colptr_(i);}


    Subscript    num_cols() const { return m_;}
    Subscript    num_rows() const { return n_; }

    Subscript          dim(Subscript i) const 
    {
#ifdef TNT_BOUNDS_CHECK
      BIASASSERT( 1 <= i );
      BIASASSERT( i <= 2 );
#endif
      if (i==1) return m_;
      else if (i==2) return m_;
      else return 0;
    }

    Subscript          num_nonzeros() const {return nz_;};
    Subscript          lbound() const {return 1;}



    Fortran_Sparse_Col_Matrix& operator=(const 
      Fortran_Sparse_Col_Matrix &C)
    {
      val_ = C.val_;
      rowind_ = C.rowind_;
      colptr_ = C.colptr_;
      nz_ = C.nz_;
      m_ = C.m_;
      n_ = C.n_;

      return *this;
    }

    Fortran_Sparse_Col_Matrix& newsize(Subscript M, Subscript N, 
      Subscript nz)
    {
      val_.newsize(nz);
      rowind_.newsize(nz);
      colptr_.newsize(N+1);
      return *this;
    }
  };

  template <class T>
    ostream& operator<<(ostream &s, const Fortran_Sparse_Col_Matrix<T> &A)
  {
    Subscript M=A.num_rows();
    Subscript N=A.num_cols();

    s << M << " " << N << " " << A.num_nonzeros() <<  endl;


    for (Subscript k=1; k<=N; k++)
    {
      Subscript start = A.col_ptr(k);
      Subscript end = A.col_ptr(k+1);

      for (Subscript i= start; i<end; i++)
      {
        s << A.row_ind(i) << " " << k << " " << A.val(i) << endl;
      }
    }

    return s;
  }



} // namespace TNT

#endif  
/* FCSCMAT_H */