\\ Solving Ordinary Differential Equations Using TACS-P2.

{ Van der Pol Oscillator  
         dx/dt = y    dy/dt = u(1-x^2)y-x   u = 1 K()
}

pub VDPOL   4 11 EULER  5 4 EULER  6 5 SQR  7 6 -REF SUM  8 1 K() 7 POT
                    9 4 8 MULT  10 9 5 SUM  11 10 INV  ;

pub (VDPOL)  
     8 NODES 20 >DT  20 >COMINT  10000 1 >K()
     5 200000  4 0 ASSIGN-IC    4 5 OUT-NODES  ;
         
REVECTOR model VDPOL
REVECTOR output PLOTY
SETPAR
(VDPOL)
gph2
CHECK  -- display initial state variable values  1M = 1.0

   4-  0            
   5-   -200000
   6-   40000
   7-   -960000
   8-   -960000
   9-  0
  10-  200000
  11-  200000

 
800 SRUN    -- execute model generates and plots 800 values vs time
    K1 Values: red > 500   blue .> 2000  yellow > 10000