How to make an X by 3 matrix into a grid of points
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So currently I have a 262014x3 matrix that has 262014 coordinates of an image.
To be able to use this for my application it has to be a 3D matrix of binary points. So I want to put a point in a, let's say, 512x512x512 matrix (I know, I'll lose a lot of definition, that's not the concern), how would I go about that?
Just a side note, the initial matrix was made by using stlread (as found here http://www.mathworks.com/matlabcentral/fileexchange/29906-binary-stl-file-reader) And I'm only using the coordinates of the vertices.
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Image Analyst
on 22 Jun 2014
Try this:
m3d = false(512,512,512); % Initialize binary image.
for row = 1 : size(coordinates, 1)
row = coordinates(row, 1);
col = coordinates(row, 2);
slice = coordinates(row, 3);
m3d(row, col, slice) = true;
end
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John D'Errico
on 22 Jun 2014
I'm confused. Subtract the min, then multiply by 511/(max - min), add 1. This will scale it to 1-512. Then round.
If you are truly memory limited, then use a bit smaller matrix.
If you really just want to visualize the points as a scatter cloud, then why not use plot3 in one call? If your goal is really to visualize this as an object, then use an alpha shape, or a convex hull if the set is convex.
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