function res = twobc(ya,yb)
%TWOBC  Evaluate the residual in the boundary conditions for TWOBVP.
%
%   See also TWOODE, TWOBVP.

%   Jacek Kierzenka and Lawrence F. Shampine
%   Copyright 1984-2000 The MathWorks, Inc. 
%   $Revision: 1.2 $  $Date: 2000/06/01 03:16:21 $

res = [    ya(1) 
        yb(1) + 2 ];
