public double ItensDistintos(int coluna)
        {
            double result = 0;

            result = Linhas.Select(x => this[x, coluna]).Distinct().Count();

            return(result);
        }
 public IEnumerable <object> Itens(int coluna)
 {
     return(Linhas.Select(x => this[x, coluna]));
 }