Clear Filters
Clear Filters

Plotting 3D by rotate 2D plot around y-axis

21 views (last 30 days)
I have a question to draw a 3D cup of coffe (no need to draw a handle). I think to be easy we need to draw 2 parabol ( inner and outter ) , the upper bound and bottom bound, then rotate that 2D plot around y-axis, but I dont have any idea and knowledge to do that, is there another way ? Can anyone help me with this, many thanks

Accepted Answer

Star Strider
Star Strider on 23 Mar 2023
Probably the easiest way is to define a cylinder and a shape vector —
yv = [linspace(0.3, 1, 50)];
ys1 = yv.*exp(-1.75*yv)*5;
ys2 = (1-exp(-25*(yv-0.3)))*0.7;
plot(ys1, yv)
hold on
plot(ys2, yv)
hold off
% xlim([0 1.5])
axis ('equal')
[X1,Y1,Z1] = cylinder(ys1,50);
[X2,Y2,Z2] = cylinder(ys2,50);
surf(X1,Y1,Z1, 'EdgeColor','interp', 'FaceAlpha',0.5) % Outer Surface
hold on
surf(X2,Y2,Z2, 'EdgeColor','interp') % Inner Survface
patch([X1(end,:) X2(end,:)], [Y1(end,:) Y2(end,:)], [Z1(end,:) Z2(end,:)], 'r', 'EdgeColor','r') % Top Rim
patch([X1(1,:) X2(1,:)], [Y1(1,:) Y2(1,:)], [Z1(1,:) Z2(1,:)], 'b', 'EdgeColor','b') % Lower Surface
hold off
This demonstrates the construction approach, and setting the outer ‘FaceAlphs’ value to shows the internal structure as well.
Experiment with the ‘ys1’ and ‘ys2’ shape vectors to get the result you want. To get the inner and outer thicknesses, it will likely be necessary to use two cyllinder objects with different shapes, and the hold function to plot both of them on the same axes. The patch call creating the top rim will autoomatically adapt to whatever the inner and outer contour functions are. Another patch call can provide a solid lower surface as well, if that is necessary. (I use the turbo colormap her because I like it. Choose the appropriate colormap for your plot.)
Tuan on 24 Mar 2023
thank you a lot, that is all i need , hope you the best <3
Star Strider
Star Strider on 24 Mar 2023
As always, my pleasure!
Thank you! You, too!

Sign in to comment.

More Answers (1)

KSSV on 23 Mar 2023
  1 Comment
Tuan on 23 Mar 2023
Thanks but this still a static image, what i mean is create a 3D object with this

Sign in to comment.


Find more on Contour Plots in Help Center and File Exchange


Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!