define new variables based on clustering results

I have some variables, say

X_1, x_2, x_3, x_4, x_5,x_6.

with related matrix of n obeservation X. I have done spectral clustering

idx = spectralcluster(X,k)

to find the clusters of variables. Assume for k=3, the index set is = 2,1,1,3,2,3. Now I want to define new variables

y_1, y_2, y_3 , where y_1={x_2,x_3}, y_2={x_1,x_5}, y_3={x_4,x_6}.

for each clusters. Is there any solution without using for loop.

Answer 1

[Raunak Gupta]

Hi,

From the example in the question I understand you have matrix with 6 observation, and you are clustering them into 3 groups. The new variables can be assigned by simply indexing matrix X with corresponding value. Below example might help.

% X = [x_1;x_2;x_3;x_4;x_5;x_6]; 
idx = spectralcluster(X,k); 
y_1 = X(idx==1,:); 
y_2 = X(idx==2,:); 
y_3 = X(idx==3,:); 

[Hamed Jalali]

Thanks for your answer. I used the below command:

y_i=X(find(idx==i));

where i is the index of the cluster. It similar to your answer.