Take the data out after using Kmeans Clusering

Hi, i tried to used Kmeans Clustering from an Excel files and after Clustering I dont know how to take the data of each Cluster. and i use 5 cluster. the plot show 5 cluster but only 3 colors. Please help me.Thanks

clear all
close all
clc
[num,txt,raw] = xlsread('ClusteringData.xlsx')
figure;
X=cell2mat(raw);
plot(X(:,2),X(:,1),'.');
[idx,C]= kmeans(X,5);
figure
title 'Kmeans Clustering';
xlabel 'Wing speed'; 
ylabel 'Power';
gscatter(X(:,2),X(:,1),idx,'bgm')
hold on
plot(C(:,2),C(:,1),'kx')
legend('Cluster 1','Cluster 2','Cluster 3','Cluster 4','Cluster 5','Cluster Centroid')

Answer 1

[Image Analyst]

Looks right off the top of my head, though you forgot to attach 'ClusteringData.xlsx' so we can't test it with your actual data.

However I don't see gscatter having an option with exactly 4 inputs in the documentation. What is 'bgm'? Colors? Shouldn't you be specifying 5 colors, not three, like 'bgmcr' or something? If you only specify 3 it will use b for class 1 and 4, and g for class 2 and 5 making it look like there are only 3 classes, not 5. Or just leave out your 4th argument altogether.

[Huy Cao]

clear all

close all

clc

[num,txt,raw] = xlsread('ClusteringData.xlsx')

figure;

X=cell2mat(raw);

plot(X(:,2),X(:,1),'.');

[idx,C]= kmeans(X,5);

figure

title 'Kmeans Clustering';

xlabel 'Wing speed';

ylabel 'Power';

gscatter(X(:,2),X(:,1),idx,'bgm')

hold on

plot(C(:,2),C(:,1),'kx')

legend('Cluster 1','Cluster 2','Cluster 3','Cluster 4','Cluster 5','Cluster Centroid')

[Huy Cao]

This í the first time i use matlab. that's is from the workspace :(

[Image Analyst]

Not sure why you did not take my suggestion. Here, I show it works if you do:

clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
clear;  % Erase all existing variables. Or clearvars if you want.
workspace;  % Make sure the workspace panel is showing.
[num,txt,raw] = xlsread('ClusteringData.xlsx');
figure;
X=cell2mat(raw);
plot(X(:,2),X(:,1),'.');
[assignedClasses, classCentroids]= kmeans(X,5);
figure
title 'Kmeans Clustering';
xlabel 'Wing speed'; 
ylabel 'Power';
gscatter(X(:,2),X(:,1),assignedClasses,'bgmrc')
hold on
plot(classCentroids(:,2),classCentroids(:,1),'kx')
legend('Cluster 1','Cluster 2','Cluster 3','Cluster 4','Cluster 5','Cluster Centroid')

[Huy Cao]

I did it. Thank youuuu ^^

[Image Analyst]

You're welcome. Thanks for Accepting the answer.

As you know the ordering of classes in kmeans is random. If you need to, or want to, reorder class numbers according to some criteria (like your x centroid value), see the attached example. Let me know if you can't figure it out.