split a matrix into two matrices according to some rule

Question

Alberto Acri 2024-2-12

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2081251-split-a-matrix-into-two-matrices-according-to-some-rule

评论： Cris LaPierre 2024-2-12

采纳的回答： Cris LaPierre

matrix.mat

在 MATLAB Online 中打开

How can I generate two separate matrices, one containing the coordinates of line A and the other of line B?

load matrix
figure
plot3(matrix(:,1),matrix(:,2),matrix(:,3),'k.','Markersize',5);
axis equal
grid off

I wanted to try this way but it does not seem the best way.

% range
xRange = [xmin xmax];
yRange = [ymin ymax];
zRange = [zmin zmax];
% indices of points in the range
idx = matrix(:,1) >= xRange(1) & matrix(:,1) <= xRange(2) & ...
    matrix(:,2) >= yRange(1) & matrix(:,2) <= yRange(2) & ...
    matrix(:,3) >= zRange(1) & matrix(:,3) <= zRange(2);
select_matrix = [matrix(idx,1), matrix(idx,2), matrix(idx,3)];

5 个评论
显示 3更早的评论隐藏 3更早的评论

Alberto Acri 2024-2-12

Hi Stephen! sorry, I realised I had not installed 'Image Processing Toolbox'!

Alberto Acri 2024-2-12

I wanted to know if there is a way to get the subdivision! I don't have any 'rules' at the moment!

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Cris LaPierre 2024-2-12

2
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2081251-split-a-matrix-into-two-matrices-according-to-some-rule#answer_1407261

编辑：Cris LaPierre 2024-2-12

在 MATLAB Online 中打开

matrix.mat

I would look into clustering. Here is an attempt that uses dbscan, a spectral clustring algorithm included in the Statistics and Machine Learning Toolbox.

You can learn more about this and other clustering techniques in our Practical Data Science with MATLAB specialization on Coursera. It's free to enroll. Here is a link to the video Introdcution to Clustering Algorithms.

https://www.coursera.org/lecture/feature-engineering-matlab/introduction-to-clustering-algorithms-V9PjS

load matrix.mat

% view the raw data

plot3(matrix(:,1),matrix(:,2),matrix(:,3),'k.','Markersize',5);

% use dbscan to identify clusters

idx = dbscan(matrix,1.5,5);

gscatter(matrix(:,1),matrix(:,2),idx)