function [penpair, unstable]=PenaltyConstrain(penpair,grids,materials,inputs)
%PENALTYCONSTRAIN - returns 0
%
%   there is no unstable element between grids
%
%   Usage:
%      [penpair, unstable]=PenaltyConstrain(penpair,grids,materials,inputs)
% 
%   See also PENALTYCREATEKMATRIX, PENALTYCREATEKMATRIX

unstable=0;

