未定義的函數(shù)或變量 'drawnow'。

pic_num = 1;for fai = 0:0.05:pi*2
   %----------------------------------------------------------------------
   % 這里你隨便寫你的代碼 出圖到f = figure(1);
   %----------------------------------------------------------------------
   f = figure(1);    
   plot(sin(1:0.01:10+fai))
   drawnow
   %----------------------------------------------------------------------
   F=getframe(gcf);
   I=frame2im(F);
   [I,map]=rgb2ind(I,256);
   if pic_num == 1
       imwrite(I,map,'test.gif','gif','Loopcount',inf,'DelayTime',0.05);
   else
       imwrite(I,map,'test.gif','gif','WriteMode','append','DelayTime',0.05);
   end
   pic_num = pic_num + 1;
   %----------------------------------------------------------------------end