plot transperant 3d sphere

HI.

How do I plot a transperant sphere within an existing 3d plot in which I already have ploted some analytical results?

the sphere need to have center in: x=16,55 y=14,85 z=9,15 and r=24,04

the x-axe has dobbelt unit compaired with y and z.

schal I use sphere or scatter3?

reguards Dorrit

Answer 1

[Dorrit]

I want the grid lines but no color betwin the grid, because i have som point plotted that i wand to see insiden the sphere.

[Andrew Newell]

See above for a demo of this.

[Patrick Kalita]

In that case, you want to set the 'FaceColor' to 'none' (and you can forgo setting 'FaceAlpha'). I've edited my answer.

[Dorrit]

I have tryed what you said, but i get a sphere in 2d in a seperat plot and not in the same 3d plot that i have alredy maid with my other set of data.-why?- I use hold on commando.

[Andrew Newell]

If you're referring to my answer, take out the FIGURE command. In general, it's a good idea to add your comments to the appropriate answer.

[Matt Fig]

I must admit, this really was the best answer to the original question. ;)

[Dorrit]

pleas give me a chance to learn how this site works before you juds me.

I just got the program and have never worked with it before and my english is not very good.

I,m more use to use Wolfram Matematica

[Andrew Newell]

I quite understand how easy it is to click the wrong Accept This Answer button, so I'm not judging. I would recommend, however, that you vote for the good answers below.

Answer 2

[Sean de Wolski]

One way:

Make a binary sphere using the formula for a sphere: http://matlab.wikia.com/wiki/FAQ#How_do_I_create_a_circle.3F

Then take calculate its isosurface using the isosurface function and make a patch of that with a low facealpha. E.g:

S = formula_for_a_sphere_applied;
[fv] = isosurface(S,0);
patch(fv,'facecolor','g','facealpha',0.2,'edgecolor','none');

Answer 3

[Andrew Newell]

As you suggested yourself, you can use sphere to generate the sphere:

r = 24.04;
[x,y,z] = sphere(50);
x0 = 16.5; y0 = 14.85; z0 = 9.15;
x = x*r + x0;
y = y*r + y0;
z = z*r + z0;

% Then you can use a surface command as Patrick suggests:

figure
lightGrey = 0.8*[1 1 1]; % It looks better if the lines are lighter
surface(x,y,z,'FaceColor', 'none','EdgeColor',lightGrey)
hold on

I'm in an artistic mood, so here is a ring of spheres inside.

r = 15;
theta = (0:.2:6)/3*pi;
x = r*cos(theta) + x0;
y = r*sin(theta) + y0;
z = z0*ones(size(x));
plot3(x,y,z)
I = 1:5:26;
h = plot3(x(I),y(I),z(I),'o','MarkerFaceColor','b','MarkerSize',24);

axis equal % so the sphere isn't distorted
view([1 1 0.75]) % adjust the viewing angle
zoom(2)

[Dorrit]

think I got it now. thanks

Answer 4

[Patrick Kalita]

The best way to do this is to just use the surface command, given that it is relatively easy to generate the x, y, and z data that define a sphere.

Here's an example:

% Generate the x, y, and z data for the sphere
r = 5 * ones(50, 50); % radius is 5
[th, phi] = meshgrid(linspace(0, 2*pi, 50), linspace(-pi, pi, 50));
[x,y,z] = sph2cart(th, phi, r);
x = x + 16;  % center at 16 in x-direction
y = y + 40;  % center at 40 in y-direction
z = z + 2;   % center at 2 in z-direction

% Let's say that this is how we make the existing 3D plot
surf(peaks);

% Now we use the surface command to add the sphere. We just need to set the FaceColor as desired.
surface(x,y,z,'FaceColor', 'none')