```--- a
+++ b/porcentual.m
@@ -0,0 +1,52 @@
+## Copyright (C) 2009 Esteban Cervetto <estebancster@gmail.com>
+##
+## Octave is free software; you can redistribute it and/or modify it
+## the Free Software Foundation; either version 3 of the License, or (at
+## your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+## General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, see
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{M} =} porcentual (@var{a}, @var{dim})
+## Auxiliar funcion. Calcs de porcentual distribution by cols (@var{a}=1) or rows (@var{a}=2)
+## of the matrix @var{a}
+## @end deftypefn
+
+## Author: Act. Esteban Cervetto ARG <estebancster@gmail.com>
+##
+## Maintainer: Act. Esteban Cervetto ARG <estebancster@gmail.com>
+##
+## Created: jul-2009
+##
+## Version: 1.1.0
+##
+## Keywords: actuarial reserves insurance bornhuetter ferguson chainladder
+
+function [M] = porcentual (a,dim)
+
+if (nargin==0)
+ usage("no data");
+end
+
+[m,n] = size(a);
+
+if (nargin == 1)
+ M = a./sum(sum(a));
+else
+ if (dim ==1)
+ M = a./ (ones(1,m)'*sum(a));
+ elseif (dim==2)
+ M = (a'./ (ones(1,n)'*sum(a')))';
+ else
+ usage("invalid dimension");
+end
+
+end
```