function yprime = nndpend(t,y)
%NNDPEND Dynamical model of a pendulum.
%	
%	NNDPEND(T,Y)
%	  T - Time
%	  Y - State = [angle; angular velocity]
%   Returns Derivative of state vector.

% $Revision: 1.2 $
% Copyright (c) 1992-1998 by PWS Publishing Company and The MathWorks, Inc.
% First Version, 8-31-95.

%==================================================================

yprime = zeros(2,1);

yprime(1) = y(2);
yprime(2) = -sin(y(1)) - 0.2*y(2);
