How to generate uniformly distributed points inside the volume of frustrum with base radius R and tip radius r and with a height of h.
3 visualizzazioni (ultimi 30 giorni)
Mostra commenti meno recenti
anuradha verma
il 12 Nov 2022
Commentato: anuradha verma
il 12 Nov 2022
I want to generate points inside the volume of a frustrum which is at a certain height h1 from (0,0,0) and the axis of frustrum is parallel to z-axis.
0 Commenti
Risposta accettata
Bruno Luong
il 12 Nov 2022
Modificato: Bruno Luong
il 12 Nov 2022
Here we go
r = 1;
R = 2; % must be > r
h = 3;
if R <= r
error('Non valid parameter')
end
Zmin = r*h/(R-r); % Position where the frustrum starts
Zmax = R*h/(R-r); % Position where the frustrum ends
N = 1e4; % Number of point
zr = (Zmin/Zmax).^3;
z = (zr + (1-zr)*rand(1,N)).^(1/3);
rho = R*sqrt(rand(1,N)).*z;
theta = (2*pi)*rand(1,N);
x = rho.*cos(theta);
y = rho.*sin(theta);
z = Zmax*(1-z);
scatter3(x,y,z,'.');
axis equal
Più risposte (1)
Image Analyst
il 12 Nov 2022
OK, but do you have a question? I'm sure you used
n = 10000; % Whatever. It's the number of points
x = 2*R*rand(n, 1)
y = 2*R*rand(n, 1);
z = h1 * rand(n, 1);
to generate uniformly distributed points in the rectangular volume. And then you probably threw out points outside the frustrum (truncated cone) volume by looking at each point's radius and the radius of the frustrum at that z level. But what is your question? Is this homework, or is there a real world use case for this?
Vedere anche
Categorie
Scopri di più su 3-D Volumetric Image Processing in Help Center e File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!