ex_fill1.cpp

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// -*- c++ -*- //
/***************************************************************************
 -   begin                : 2003-09-05
 -   copyright            : (C) 2003 by Gunter Winkler
 -   email                : guwi17@gmx.de
 -   This program is free. Use it at your own risk                
 ***************************************************************************/

#include <iostream>

#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/matrix_sparse.hpp>
#include <boost/numeric/ublas/io.hpp>

using namespace boost::numeric::ublas ;

using std::cout;
using std::endl;

int main(int argc, char *argv[])
{
  const size_t size = 10;
  // define a row-major sparse matrix
  compressed_matrix<double>  A(size, size);

  for (size_t i=0; i<A.size1(); ++i)    {
        if (i>=1) { 
          A.push_back(i,i-1,-1.0); 
        }
        A.push_back(i,i,4);
        if (i+1<A.size2()) { 
          A.push_back(i,i+1,-1.0); 
        }
  }
  
  cout << "A = " << A << "(nonzeros: " << A.filled() << ")" << endl;

  return EXIT_SUCCESS;
};

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