# How to move the axes so that they start from the center of the sphere (0,0,0)

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Atom on 11 Jun 2022
Commented: Atom on 12 Jun 2022
()1 How to move the axes so that they start from the center of the sphere (0,0,0)
(2) If I only want to keep the boundary curve and remove the interiors, what to do?
R = 1 ;
theta = linspace(0,2*pi) ;
phi = linspace(0,pi) ;
[T,P] = meshgrid(theta,phi) ;
X1 = R*cos(T).*sin(P) ;
Y1 = R*sin(T).*sin(P) ;
Z1 = R*cos(P) ;
zlim([0,5])
surf(X1,Y1,Z1,'EdgeColor','r', 'FaceColor', 'none', 'FaceAlpha', .5) ; Atom on 12 Jun 2022
The interior is like as the post of Image Analyst (convhulln)

Star Strider on 11 Jun 2022
Try something like this —
R = 1 ;
theta = linspace(0,2*pi) ;
phi = linspace(0,pi) ;
[T,P] = meshgrid(theta,phi) ;
X1 = R*cos(T).*sin(P) ;
Y1 = R*sin(T).*sin(P) ;
Z1 = R*cos(P) ;
zlim([0,5])
surf(X1,Y1,Z1,'EdgeColor','r', 'FaceColor', 'none', 'FaceAlpha', .5, 'EdgeAlpha',0.5) ;
hold on
plot3([0 0],[0 0],zlim, '-k', 'LineWidth',1.5)
xline(0, '-k', 'LineWidth',1.5)
yline(0, '-k', 'LineWidth',1.5)
Ax = gca;
xt = Ax.XTick;
yt = Ax.YTick;
zt = Ax.ZTick;
Ax.Visible = 'off';
plot3([xt; xt], ones(2,numel(xt)).*[-1;1]*0.1, zeros(2,numel(xt)), '-k')
plot3(ones(2,numel(xt)).*[-1;1]*0.1, [yt; yt], zeros(2,numel(xt)), '-k')
plot3(ones(2,numel(xt)).*[-1;1]*0.1, zeros(2,numel(xt)), [zt; zt], '-k')
hold off
text(xt, zeros(size(xt)), zeros(size(xt)), compose(' %.1g',xt), 'Horiz','left', 'Vert','middle', 'Rotation',-35)
text(zeros(size(yt)), yt, zeros(size(yt)), compose(' %.1g',yt), 'Horiz','left', 'Vert','middle', 'Rotation',30)
text(zeros(size(zt)), zeros(size(zt)), zt, compose(' %.1g',zt), 'Horiz','left', 'Vert','middle', 'Rotation',-10)
axis('equal') .

Image Analyst on 11 Jun 2022
The usual way is
ax = gca;
ax.XAxisLocation = "origin";
ax.YAxisLocation = "origin";
However it doesn't seem to work for this 3-D plot. Not sure why. It does work for 2-D plots though.
Atom on 11 Jun 2022
Edited: Atom on 11 Jun 2022
No..it is not working