Centroid plotting k-means

Hi guys, I am currently working on a k-means problem. I am struggling to plot the Centroid provided. I currently get the following error messages: Error using scatter3 (line 45) C must be a single color, a vector the same length as X, or an M-by-3 matrix.

Error in import_excelv4 (line 86) scatter3(U(:,1), U(:,2), U(:,3), 100, clr,'Marker','o','LineWidth',3)

My code is as shown bellow and my data is attached to this question

if true
  % %%
%importar dados do excel
imp = xlsread('Academia.xlsx');

%% Loop Kmeans K clusters

k=20

CH=zeros(1,k); SH=zeros(1,k); DB=zeros(1,k); SUB=zeros(1,k); RR=zeros(80,k); % eva = evalclusters(x,clust,criterion) for i=1:k [idx,C]=kmeans(imp,i,'MaxIter',1000000); %C=centroides % Como pegar o valor de idx ? RR(:,i)=idx T{i}=C eva = evalclusters(imp, idx, 'CalinskiHarabasz') CH(1,i)=eva.CriterionValues eva2 = evalclusters(imp, idx, 'Silhouette') SH(1,i)=eva2.CriterionValues eva3 = evalclusters(imp, idx, 'DaviesBouldin') DB(1,i)=eva3.CriterionValues end

%% Calculos das metricas CH(1,1)=0 % % Descobrir as diferenças entre os valores de CH while i>1 SUB(1,i)=CH(1,i)-CH(1,i-1); i=i-1; end SUB(1,1)=0

%Achar o pulo maximo entre os clusters para o valor de CH: [V,N]=max(SUB) % Por algum motivo está pulando a célula vazia e fornecendo valor incorreto

 SH
 %SHF=cell2mat(SH)
 [V2,N2]=max(SH) %Valor mais próximo de 1

 DB
 %DBF=cell2mat(DB)
 [V3,N3]=min(DB) %Valor mais próximo de 0
 %%Melhor qtd de clusters

if (N==N2) && (N2==N3) disp('CH=SH=DB') N N2 N3 i=N; Z=RR(:,i) y=xlswrite('Academia_target.xlsx',Z,'D2:D81'); U=T{i} elseif N2==N3 disp('SH=DB') elseif N==N3 disp('CH=DB') elseif N==N2 disp('CH=SH') else disp('Todas as métricas forneceram valores diferentes') end

%% Plotar os dados:

    [numInst,numDims] = size(imp);
    %# show points and clusters (color-coded)
    clr = lines(k);
    figure, 
    scatter3(imp(:,1), imp(:,2), imp(:,3), 36, clr(Z,:), 'Marker','.')
    hold on
    scatter3(U(:,1), U(:,2), U(:,3), 100, clr,'Marker','o','LineWidth',3)
    hold on
    view(3), axis vis3d, box on, rotate3d on
    hold on
    xlabel('flexibilidade'), ylabel('velocidade'), zlabel('forca')
    hold off
  end

I dont understand the error messages since I am using U as a matrix for the centroids and only a single color.

Can someone please help me ?

Thanks in Advance !

Answer 1

[Ced]

Hi

It looks like you got a bit mixed up in your indices:

clr = lines(k);

creates a matrix with k colors, but you only have i <= k centroids (Since U = T{i} with i == N <= k).

Using

    clr = lines(i);

solves the issue.