# Plotting a sphere consisting of planes

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Paul Leon Alfred Berner on 6 Apr 2020
Commented: darova on 20 Apr 2020
Hi folks,
i want to plot a sphere consisting of triangular planes. The cartesian coordinates of the planes are given by their respective corner points A, B and C which have their own 3D-coordinates A(Ax, Ay, Az), B(Bx, By, Bz) and C(Cx, Cy, Cz). The usual plot-Function does not produce reasonable results.
Does anyone has a suggestion?

darova on 6 Apr 2020
Can you show some of your attempts? Do you have a picture of the result? Can you make a simple drawing or something?
Paul Leon Alfred Berner on 6 Apr 2020
The plotted result should be similar to the picture from the description of the icosphere-function in the MathWorks File Exchange (see attachement).
My attempt:
A = surfacessphere; %coordinates of the triangular faces are stored in the surfaces_sphere.txt
Ax = A(:,5); %
Ay = A(:,6); %Defining columns of Matrix A as columnvectors
Az = A(:,7); %
Bx = A(:,8); %
By = A(:,9); %Defining columns of Matrix A as columnvectors
Bz = A(:,10); %
Cx = A(:,11); %
Cy = A(:,12); %Defining columns of MAtrix A as columnvectors
Cz = A(:,13); %
plot3(Ax,Bx,Cx); %
plot3(Ay,By,Cy); %Plotting
plot3(Az,Bz,Cz); %

darova on 6 Apr 2020
Use patch for this problem
% create data of format
% Ax Ay Az
% Ax Ay Az
% ...
% Bx By Bz
% Bx By Bz
% ...
% Cx Cy Cz
% Cx Cy Cz
% ...
fv.vertices = reshape(A(:,5:13),[],3);
% create connection list of format
% 1 n+1 2n+1
% 2 n+2 2n+2
% 3 n+3 2n+3
% ...
n = size(A,1);
fv.faces = [1:n; (1:n)+n; (1:n)+2*n]';
fv.facecolor = 'yellow';
patch(fv)

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darova on 7 Apr 2020
Everything is the same. Why shouldn't it be different? The script i wrote i just plot triangles, it doesn't know what shape is. Are you asking of how to read data?
Paul Leon Alfred Berner on 20 Apr 2020
Unfortunately the result of the submitted script looks like the attacheted picture and not like the cylinder in the xz-plane (attachement). Reading data is not the problem:) (i think)
darova on 20 Apr 2020
I made a wrong script, sorry. Try this:
A1 = importdata('surfaces_cylinder.txt');
A = A1.data;
ii = [5 8 11];
patch(A(:,ii)',A(:,ii+1)',A(:,ii+2)','y')
axis vis3d