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-- ---------------------------------------------------------------------
--
-- $Id: 2nd_order_ode.ams,v 1.1 2002-03-27 22:11:17 paw Exp $
-- $Revision: 1.1 $
--
-- ---------------------------------------------------------------------

entity VanDerPol is 
    generic (m: real := 1.0); 
end entity VanDerPol; 

architecture SecondOrderODE of VanDerPol is 
quantity x:real;
begin 
    -- the break statement sets the initial conditions 
    break x => 0.0, x'dot => 0.1; 

    -- second-order Van Der Pol ODE 
    x'dot'dot == -x -m*(x*x - 1.0)*x'dot;
end architecture SecondOrderODE;