Animation using plot inside for loop

Question

Garrett Herbst 2018-10-8

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/422908-animation-using-plot-inside-for-loop

评论： Rahul Wadhwani 2022-8-30

I am trying to create an animation by using the plot function inside of a for loop. No matter what I do, I just get back the same still figure that opens. This figure opens over and over again when I close it.

 figure(5)
for n = 1:1000
    pos = xout(n,1)
    x_origin = 0;
    y_origin = 0;
    x_bob = 0.75*sin(pos);
    y_bob = -0.75*cos(pos);
    plot([x_origin,x_bob],[y_origin,y_bob])
    axis equal
    xlim([-2 2])
    ylim([-2 2])
    drawnow
end

'xout' is a matrix with the angle values of a pendulum in the first column.

3 个评论
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Image Analyst 2018-10-9

I get a line swinging around like hands on a clock. Maybe put a pause(0.1) at the bottom of the loop to slow it down if you can't see it move.

Stephen Wilkerson 2018-12-1

Yes this: works fine as a .m file, but if put in a live script does not work, is there a way to animate a live script?

figure(5)

for n = 1:100

x_origin = 0;

y_origin = 0;

x_bob = 0.75*sin(n);

y_bob = -0.75*cos(n);

plot([x_origin,x_bob],[y_origin,y_bob])

axis equal

xlim([-2 2])

ylim([-2 2])

drawnow

end

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Answer 1

ANKUR KUMAR 2018-10-9

3
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/422908-animation-using-plot-inside-for-loop#answer_340417

在 MATLAB Online 中打开

clc
clear
h=figure
for n = 1:10
    x_origin = 0;
    y_origin = 0;
    x_bob = 0.75*sin(n);
    y_bob = -0.75*cos(n);
    plot([x_origin,x_bob],[y_origin,y_bob])
    axis equal
    xlim([-2 2])
    ylim([-2 2])
    make_animation( h,n,'sample_animation.gif' )
    pause(0.2) %you can enter the time in pause to change the loop
end
function make_animation( h,index,filename )
drawnow
frame = getframe(h);
im = frame2im(frame);
[imind,cm] = rgb2ind(im,256);
if index == 1
    imwrite(imind,cm,filename,'gif', 'Loopcount',inf);
else
    imwrite(imind,cm,filename,'gif','WriteMode','append');
end
end

If you are using older version than 2016a, then write make_animation in separate function and then run the program, as older version of MATLAB doesn't support writing functions inside in the script.