Point cloud with Matlab

How to divide a point cloud in four quadrants? Please help me with the code in matlab.

[Walter Roberson]

Use pca() to find the orientation of the planes, and use the centroid of the point cloud as the center of the planes

Answer 1

[Dev]

Hi @QS,

To divide a point cloud into four quadrants, we can loop through each point using a ‘for’ loop and assign it to a quadrant. I have added a reference code snippet below which can be used inside this loop to help us achieve the same-

% Assign each point to the respective quadrant
if x >= origin(1) && y >= origin(2)
    quadrant1 = [quadrant1; x, y]; % Quadrant I
elseif x < origin(1) && y >= origin(2)
    quadrant2 = [quadrant2; x, y]; % Quadrant II
elseif x < origin(1) && y < origin(2)
    quadrant3 = [quadrant3; x, y]; % Quadrant III
else
    quadrant4 = [quadrant4; x, y]; % Quadrant IV
end

To visualize the point cloud, we can use the ‘scatter’ function in MATLAB. I have attached an example output of a point cloud divided into quadrants below, for your reference.

For more information regarding the usage of the ‘for’ loop and the ‘scatter’ function, please refer to the documentation links below-

for- https://www.mathworks.com/help/releases/R2024b/matlab/ref/for.html

scatter- https://www.mathworks.com/help/releases/R2024b/matlab/ref/scatter.html

Hope this solves the query.