// ===  FUNCTION  ======================================================================
//         Name:  print_array
//  Description:  Print an array with one dimension.
//                Use
//                  print_array<T,width,precision>( *matrix, n1*n2, n2, "matrix" ); 
//                for
//                  T matrix[n1][n2];   
// =====================================================================================
  template < class T, unsigned width, unsigned precision >
void print_array ( T      *array,               // array to print
                   int     n,                   // number of elements to print
                   int     nrow,                // number of elements per row
                   string  arrayname            // array name
                   )
{
  string line(" index | content\n ------+-");

  cout  << "\n\n  array \"" << arrayname << "\", length " << n << endl << endl;
  cout  << line.append(width*nrow, '-');
  for ( int i=0; i<n; i+=1 ) {
    if( i%nrow == 0 )
      cout  << endl << setw(6) << i << " | ";
    cout  << setw(width) << fixed << setprecision(precision) << array[i];
  }
  cout  << endl << endl;
  return ;
}       // ----------  end of function print_double_array  ----------