dwindrootb=figure('color',[.5,.9,.9],'position',[0.1*winw,0.1*winh,0.8*winw,0.8*winh],...
       'name','閉環離散系統零極點分布','numbertitle','off','menubar','figure',...
        'resize','off');
     
     
n=length(dak);     
for i=1:n
   dek(i,i)=1;
end
n=length(da);
for i=1:n
   de(i,i)=1;
end  

dsysb=dss(da,db,dc,dd,de,dhT); 
dsysk=dss(dak,dbk,dck,ddk,dek,dhT);    
subplot(2,1,1);
pzmap(dsysb);
grid;xlabel('');ylabel('虛部');title('系統零極點圖');
subplot(2,1,2);
rlocus(dsysk);
grid;xlabel('實部');ylabel('虛部');title('系統根軌跡圖');
%subplot(2,1,2);rlocus(bnum,bden);
%grid;xlabel('實部');ylabel('虛部');title('系統根軌跡圖');