%exm111_1.m
clf reset,shg
H=axes('unit','normalized','position',[0,0,1,1],'visible','off');
set(gcf,'currentaxes',H);
str='\fontname{隸書}歸一化二階系統的階躍響應曲線';
text(0.12,0.93,str,'fontsize',13);
h_fig=get(H,'parent');
set(h_fig,'unit','normalized','position',[0.1,0.2,0.7,0.4]);
h_axes=axes('parent',h_fig,...
   'unit','normalized','position',[0.1,0.15,0.55,0.7],...
   'xlim',[0 15],'ylim',[0 1.8],'fontsize',8);

disp('按任意鍵，繼續！'),pause
h_text=uicontrol(h_fig,'style','text',...
   'unit','normalized','position',[0.67,0.73,0.25,0.14],...
   'horizontal','left','string',{'輸入阻尼比系數','zeta ='});
h_edit=uicontrol(h_fig,'style','edit',...
   'unit','normalized','position',[0.67,0.59,0.25,0.14],...
   'horizontal','left',...
   'callback',[...
      'z=str2num(get(gcbo,''string''));',...
      't=0:0.1:15;',...
      'for k=1:length(z);',...
      's2=tf(1,[1 2*z(k) 1]); ',...     
      'y(:,k)=step(s2,t);',...
      'plot(t,y(:,k));',...
      'if (length(z)>1) ,hold on,end,',...
      'end;',...
   		'hold off,']);
   
disp('按任意鍵，繼續！'),pause
h_push1=uicontrol(h_fig,'style','push',...
   'unit','normalized','position',[0.67,0.37,0.12,0.15],...
   'string','grid on','callback','grid on');
h_push2=uicontrol(h_fig,'style','push',...
   'unit','normalized','position',[0.67,0.15,0.12,0.15],...
   'string','grid off','callback','grid off');
  
disp(' '),disp('在編輯框中，填寫標量或一維數組；再按Enter鍵，就繪出曲線。')