MATLAB: I want to use plot

MATLABplot3

Hello, i want to describe 10 points, I want to use function plot3.

I have 10 points save to cell Z. one point have the coordinates[x,y,z], but I can have a multi-dimensional space. I want to make it work multidimensional space[x,y,z,k,l,m,n]

for example:

Z = 
    {1x1 cell}    {1x7 cell}    {1x2 cell}
Z{1}= [1x3 double] - has one point
Z{2}= [1x3 double]    [1x3 double]    [1x3 double]    [1x3 double]    [1x3 double] [1x3 double] - has seven points
Z{3}= [1x3 double]    [1x3 double - has two points.

i want to describe Z{1} – green, Z{2}- blue,Z{3}-red.

Thanks.

Best Answer

z={{rand(1,3)},[{rand(1,3)} {rand(1,3)} {rand(1,3)} {rand(1,3)} {rand(1,3)} {rand(1,3)} {rand(1,3)}],[{rand(1,3)} {rand(1,3)} ] }
cl='gbr'
for k=1:numel(z)
  y=cell2mat(z{k}')
  scatter3(y(:,1),y(:,2),y(:,3),'facecolr',cl(k))
  hold on
end
hold off

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x = xyz(1,:);
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"I don't want to use the sphere function because I intend to create multiple spheres and get the x,y,z values to each one of them."

The solution below contains a function produceSphereCoord() that is based on Matlab's sphere() function but doesn't produce the surface plot. At the top the script below, you can set the number of nodes each sphere will have. Then you can set the number of spheres to create. The 3D coordinates of one sphere is created with [-1,1] normalized units. It's then replicated as many times as requested and the coordinates are stored in a [n-by-3] cell array "xyz" where the columns are values of [x,y,z] coordinates and there's one row for each sphere.

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function [x, y, z] = produceSphereCoord(n)
% from matlab's sphere() function.
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theta = (-n:2:n)/n*pi;
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sintheta = sin(theta); sintheta(1) = 0; sintheta(n+1) = 0;
x = cosphi*cos(theta);
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You can then scale them as needed with the help of cellfun(). In this example, I scale the 6 spheres to 6 different sizes.

scales = {10 8 6 4 2 .5}'; 
scalesMat = repmat(scales, 1,3); 
xyzScaled = cellfun(@(n,s)n.*s, xyz, scalesMat, 'UniformOutput', false);

To plot the results,

cla()
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box on
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view(3)

Best Answer

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