public void print(PrintWriter out) 
   throws IOException {
      String temp;
      int i, j, k, size = 0;
     
      for(i = 0; i < _rows; i++) {
         for(j = 0; j < _cols; j++) {
            temp = _mat[i][j] + "";
            if(temp.compareTo("-0.0") == 0)
               temp = "0.0";
            if(temp.length() > size)
               size = temp.length();
         }
      }
      
      for(i = 0; i < _rows; i++) {
         for(j = 0; j < _cols; j++) {
            temp = _mat[i][j] + "";
            if(temp.compareTo("-0.0") == 0)
               temp = "0.0";
            for(k = 0; k < ((size - temp.length()) + 1); k++)
               out.print(" ");
            out.print(temp);
         }
         out.println();
         out.flush();
      }
   }