text: package scalaExec.Functions.Chaotic;
  
  import  numal.*; 
  
  public class VDPDiffSys extends Object 
               implements AP_diffsys_methods 
  {
   static  final   double  mu;
  
   static {
       mu = 2;
  }
      
  // Vanderpole oscillator
  public void derivative(int n, double x, double y[], double dy[])  { 
    double xx,yy; 
  
      xx=y[1];     yy=y[2];    
  
      dy[1] = yy;
      dy[2] = mu*(1-xx*xx)*yy - xx;  
      } 
   
   public void output(int n, double x[],  double xe, double y[], double dy[])  { 
  return; 
    } 
  }
  