How to rotate a 2d plot about the z axis to create a 3d object

34 次查看(过去 30 天)
Good afternoon everyone,
My goal with the code bellow is to somehow transfer the use of using a roation matrix to rotate my 2d plot about the z axis to hopefully create a closed, convex surface. The issue im having trouble with is how can this be accomplished, since originally we dont have a z coord? would we have to plot the snips of the rotation in spherical coords, then at the end transfer the spherical coords to rectangular? The code bellow will rotate a given vector about (0,0) with given degrees in 2d, how can I implement this in 3d? The 3d rotation matrix for the z axis will be at the bottom of the doc if it helps.
Thank you for the time!
Please, Please, let me know if you see anywhere I can improve my code, make it more efficent, faster, anything!
Yieldstr = 1000; % KPa, Sets the str for all following 2d Plots
minValue = -4*Yieldstr;
maxValue = 4*Yieldstr;
fidelity = Yieldstr/125; %able to use much higher fidelity in 2d
sigx = minValue:fidelity:maxValue;
sigy = sigx.';
VM = (1/(sqrt(2)) .* sqrt((sigx-sigy).^2 + (sigy).^2 +(-sigx).^2));
[x,y,~] = find(VM<Yieldstr);
PStress = [sigx(y).' sigy(x)];
A = boundary(PStress,0);
FirstC = PStress(A,1);
SecC = PStress(A,2); %all this block of code is doing is finding the boundary of our Pstress
Var = [FirstC SecC]; %then assigning it to a variable, I think it'll make it a bit easier in the future
Var = Var';
Num = length(Var(1,:));
for theta = 0:45:45
for i = 1:1:Num
S(1,1) = Var(1,i);
S(2,1) = Var(2,i);
% S(3,1) = 0;
Rz = [cosd(theta) -sind(theta); sind(theta) cosd(theta)];
P = Rz*S;
X(1,:) = P(1,:);
Y(2,:) = P(2,:);
scatter(X,Y);
hold on
end
end
hold off
%here is the rotation matrix for rotating about the z axis
%Rz = [cosd(theta) -sind(theta) 0 ; sind(theta) cosd(theta) 0; 0 0 1];

采纳的回答

Matt J
Matt J 2021-10-14
See the cylinder command.
t = 0:pi/10:2*pi;
r = 2 + cos(t);
[X,Y,Z] = cylinder(r);
plot(r,t), xlim([0,3])
surf(X,Y,Z)

更多回答(0 个)

类别

Help CenterFile Exchange 中查找有关 Labels and Annotations 的更多信息

产品


版本

R2021a

Community Treasure Hunt

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

Start Hunting!

Translated by