How can I use the AXIS EQUAL functionality for a 3D plot in MATLAB 7.4 (R2007a) ?

I would like to be able to make an option in the ‘axis equal’ functionality to select 2 axes only and have the third axis scaled automatically. The following code shows that the ‘axis equal’ functionality doesn’t scale the figure properly:

figure

t = 0:pi/50:10*pi;

subplot(1,2,1); plot3(sin(t),cos(t),t);

title('Normal');

subplot(1,2,2); plot3(sin(t),cos(t),t); 

axis equal;

title('Axis equal')

Answer 1

[MathWorks Support Team]

The ability to use the AXIS function for 3-D plots is not available in MATLAB.

To work around the issue, it is possible to scale all the three axes by using the 'DataAspectRatio' property of the axes object:

figure

t = 0:pi/50:10*pi;

subplot(1,2,1); plot3(sin(t),cos(t),t);

title('Normal');

subplot(1,2,2); plot3(sin(t),cos(t),t); 

h = get(gca,'DataAspectRatio') 

if h(3)==1

      set(gca,'DataAspectRatio',[1 1 1/max(h(1:2))])

else

      set(gca,'DataAspectRatio',[1 1 h(3)])

end

title('Axis equal')