MATLAB: How to make the Earth rotate around it’s axis in matlab

3d plotsMATLAB

So I want to represent the Earth rotating for a number of seconds from a tspan knowing that a full rotation happens in 86160 seconds. It means that for 239.33 seconds , the Earth rotates with a degree. The problem is that I don t know how to use the rotate command in a right way. This is the code:

    tspan=[0 :72000];
[X,Y,Z]=sphere(50);
R=6400000;
earth = imread('earth.jpg');
globe= surf(-X*R,Y*R,-Z*R);
image_file='earth.jpg';
cdata = imread(image_file);
set(globe, 'FaceColor', 'texturemap', 'CData', cdata,  'EdgeColor', 'none');
set(gcf,'Color','k')
set(gca, 'visible', 'off')
axis equal
view (90,0)
rotating=1; % 1 degree ever 239.33 seconds from tspan
rotate(earth, [0 1 0],1) % test to see if it's working

Best Answer

Hi Alexandru,

MODIFIED answer

I used a jpg of my own and reproduced your code, eliminating some lines that were not in use. It works really well. I am not sure what you mean by 'doesn't stay on fixed axis, moves around it'. When I run this, the globe stays in place. I am using [0 0 1] instead of [0 1 0] so that the globe rotates about the north pole. With [0 1 0] the globe is rotating about an unusual axis, but it is still staying in place and rotating about its center of mass.

[X,Y,Z]=sphere(50);
R=6400000;
globe= surf(-X*R,Y*R,-Z*R);
cdata = imread('chilis.jpg');
set(globe, 'FaceColor', 'texturemap', 'CData', cdata,  'EdgeColor', 'none');
set(gcf,'Color','k')
set(gca, 'visible', 'off')
axis equal
view (90,0)
rotate(earth, [0 0 1],1) % test to see if it's working

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