Personally, I would just use scatter3 and then look at the data from above (along the z-axis). So something like:
scatter3(x,y,z)
view(0,90)
axis equal
Modifying the datatip labels in a 2d scatter plot is also possible though:
hp = scatter(x,y);
hp.DataTipTemplate.DataTipRows(3) = dataTipTextRow('Z',z);
axis equal
The above code can be tested with the following data:
x = -1:0.1:1;
y = [sqrt(1-x.^2) -sqrt(1-x.^2)];
x = repmat(x,1,2);
z = rand(1,numel(x));
