% new DFOD scheme, comparison

clear all;close all;warning off;
ts=0.001;fs=1/ts;fn=fs/2; r= .5;
f=logspace(-2,3,200);w=2*pi*f;
s=j*w;g0m=abs(s.^r);g0p=angle(s.^r) *180/pi;
 
% ---- make comparison between Tustin+CFE and AA-CFE.
for norder=3:3
figure;
% base line plot
 [b2,a2]=tustin_cfe(norder,r,ts);
 sys2=tf(b2,a2,ts);
 [mag2,pha2]=bode(sys2,w);
 subplot(2,1,1);plot(f,mag2(1,:),'b'),grid on;hold on;
 subplot(2,1,2);plot(f,pha2(1,:),'b'),grid on;hold on;
 a=0:.25:1; plottype=[['-r '];[':c '];['--m'];['-.k'];['-Or']];
for iw=1:5
 % new 
 sys3=newdfod(norder,ts,a(iw),r);
 [mag3,pha3]=bode(sys3,w);
 subplot(2,1,1);plot(f,mag3(1,:),plottype(iw,:)),grid on;hold on;
% subplot(2,1,2);plot(f,pha3(1,:),plottype(iw,:)),grid on;hold on;
 subplot(2,1,2);plot(f,pha3(1,:)+angle( (exp(s*ts)).^(0.*r)) *180/pi,plottype(iw,:)),grid on;hold on;

end
subplot(2,1,1);plot(f,g0m,'k'),grid on;hold on;
ax=axis;ax(2)=fs/2;ax(3)=0;ax(4)=700*r;axis(ax);
subplot(2,1,2);plot(f,g0p,'k'),grid on;hold on;
ax=axis;ax(2)=fs/2;ax(3)=0;ax(4)=50*2*r;axis(ax);
legend( ['s^{0.5}: Tustin + CFE, t_s=0.001s, N=',num2str(norder)], ...
   	  ['s^{0.5}: new DFOD, t_s=0.001s, N=',num2str(norder), 'a=0'], ...
   	  ['s^{0.5}: new DFOD, t_s=0.001s, N=',num2str(norder), 'a=.25'], ...
   	  ['s^{0.5}: new DFOD, t_s=0.001s, N=',num2str(norder), 'a=.5'], ...
   	  ['s^{0.5}: new DFOD, t_s=0.001s, N=',num2str(norder), 'a=.75'], ...
   	  ['s^{0.5}: new DFOD, t_s=0.001s, N=',num2str(norder), 'a=1'], ...
        ['s^{0.5}: continuous Bode'])
end %norder