%混沌序列的產生
function x=chaosequ(inia,n)
%a=0.2;
x(1)=0.1;%動力方程的初值
%a=0.1;
%x(1)=inia;
thr_chaos=0.5;%二值化的閾值
%-----------------------------
%chaos sequence generation
%-----------------------------
for k=1:n-1,   
   if x(k)<inia&x(k)>0
      x(k+1)=x(k)/inia;
   end
   if x(k)>=inia&x(k)<=1;
      x(k+1)=(1-x(k))/(1-inia);
   end
end
%------------------------------
%binary transformation
%------------------------------
for i=1:n,
   if x(i)>thr_chaos,
      x(i)=1;
   elseif x(i)<=thr_chaos,
      x(i)=-1;
   end
end
%------------------------------
%t=linspace(0,1000,1000);
%plot(t,sequ);