[galieluo]

程序的目的是画一个一阶响应曲线

h_edit=uicontrol(gcf,'style','edit',...
'unit','normalized','position',[0.67,0.65,0.25,0.14],...
'horizontal','left',...
'callback',[...
'z=str2num(get(h_edit,"string"));',...
't=0:0.1:15;',...
'for k=1:length(z);',...
'y(:,k)=step(1,[1 2*z(k) 1],t);',...
'plot(t,y(:,k));',...
'if(length(z)>1),hold on,end,',...
'end;',...
'hold off,']);

运行提示：
??? Error: Missing variable or function.

??? Error while evaluating uicontrol Callback.

请各位高手指点一下，感激不尽。