--- a
+++ b/inst/__tito_dim__.m
@@ -0,0 +1,44 @@
+## Copyright (C) 2009-2014   Lukas F. Reichlin
+##
+## This file is part of LTI Syncope.
+##
+## LTI Syncope is free software: you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## LTI Syncope 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 LTI Syncope.  If not, see <http://www.gnu.org/licenses/>.
+
+## TODO
+
+## Author: Lukas Reichlin <lukas.reichlin@gmail.com>
+## Created: January 2014
+## Version: 0.1
+
+function [nmeas, ncon] = __tito_dim__ (P)
+
+  outgroup = P.outgroup;
+  ingroup = P.ingroup;
+  
+  ## FIXME: add checks whether indices of V and U are in ascending order
+  ##        and at the end of the outputs/inputs
+  
+  if (isfield (outgroup, "V"))
+    nmeas = numel (outgroup.V);
+  else
+    error ("tito_dim: missing outgroup 'V'");
+  endif
+  
+  if (isfield (ingroup, "U"))
+    ncon = numel (ingroup.U);
+  else
+    error ("tito_dim: missing ingroup 'U'");
+  endif
+
+endfunction