matlab画图最大化以及录制GIF动画

clc;
x = 0:0.01:1;

sz=get(0,'screensize');
figure('outerposition',sz);

filename = 'testnew51.gif';
for n = 1:0.5:10
    y = x.^n;
    plot(x,y)
    title(num2str(n));
    pause(0.5);    
    drawnow
    
    frame = getframe(1);
    im = frame2im(frame);
    [imind,cm] = rgb2ind(im,256);
    if n == 1;
        imwrite(imind,cm,filename,'gif', 'Loopcount',inf);
    else
        imwrite(imind,cm,filename,'gif','WriteMode','append');
    end
    
end