Replace function

Hello, I have the following function,

function label = litekmeans(X, k) n = size(X,2); last = 0; label = ceil(k*rand(1,n)); % random initialization while any(label ~= last) [~,~,label] = unique(label); % remove empty clusters E = sparse(1:n,label,1,n,k,n); % transform label into indicator matrix center = X*(E*spdiags(1./sum(E,1)',0,k,k)); % compute center of each cluster last = label; [~,label] = max(bsxfun(@minus,center'*X,0.5*sum(center.^2,1)')); % assign samples to the nearest centers end

I have to replace the 'unique' and the 'spdiags' function. I am allowed to use only built in functions.

I am quite new in matlab and i can't understand how those 2 functions work here.

Can anyone explain me what are they actually doing or how they work.

I will need to understand how they work so be able to replace them.

Can anyone help me? Thanks nonyt!

[nonyt]

sorry the function does not appear very well here it is again:

function label = litekmeans(X, k)

n = size(X,2);

last = 0;

label = ceil(k*rand(1,n)); % random initialization

while any(label ~= last)

[~,~,label] = unique(label); % remove empty clusters

E = sparse(1:n,label,1,n,k,n); % transform label into indicator matrix

center = X*(E*spdiags(1./sum(E,1)',0,k,k)); % compute center of each cluster

last = label;

[~,label] = max(bsxfun(@minus,center'*X,0.5*sum(center.^2,1)')); % assign samples to the nearest centers

end

[Andrew Newell]

Have you tried "doc unique"?

[Matt Fig]

First off, please go back and use the {} Code button after highlighting the code you pasted into the window, then delete your comment where you pasted it again.

Second, you can learn exactly what goes on with the UNIQUE function by typing:

edit unique

the reading the function.