named constraints which actually     
% don't exist (infinite bounds) are ignored.                            
%
%   penm.lbYbar = [1:penm.NY];
%   penm.ubYbar = [ 3 ];
%
% * [optional] *box constraints on the elements of the matrix variables*
% only elements matching patterns of |Y{}| will be taken into account if the
% matrix is empty (|[]|) it is automatically considered as |+/-Inf| accordingly
%
%   penm.lbYx{1} = - magic(3); 
%   penm.ubYx{1} = magic(3);
%   penm.lbYx{2} = sparse(5,5); 
% 