MATLAB: Comparing each vector in a cell array to another vector

cell arrayismembervectorizationvectors

Hello. I am wondering if there is an easier way to check vectors in my cell array are subsets of another given vector. I want to keep track of how many times the vectors in C are found in T, for many different T's. For example:
T = [1 2 3 4 5 6]
C = { [1 2], [3 4], [5,6], [7 8], [9, 10] }
% loop through each candidate
for j = 1:numCands
    c = Ck{j};
    % Candidate Counts. Check if candidate is a subset of the
    % current transaction
    if ismember(c,t)
       candCounts(j) = candCounts(j) + 1;
    end
    % Candidate Tail Counts. Check if the tail of the candidate is
    % a subset of the current transaction
    if ismember(c(2:end),t)
       candTailCounts(j) = candTailCounts(j) + 1;
    end
end
What I have done is loop through each member of C and check using ismember() for each element. But this gets really long when C becomes very large. I was wondering if there was any clever way of vectorization which would result in a faster runtime. I would also like to add that T can be varying sized vectors. Not sure if that information is relevant or not.
Thanks in advance!
Edit: For future references here is what I ended up doing, which is similar to what the answers suggested:
% Make all candidates into matrix for faster calculation
allCands = vertcat(Ck{:});
% Get number of columns to get where there are subsets.
[~,col] = size(allCands);
% Find locations where the candidates are subsets of the
% transactions for both the candidates and tail counts.
memb1 = ismember(allCands,t);
memb2 = ismember(allCands(:,2:end),t);
% Subset check
subCheck1 = find(sum(memb1,2) == col);
subCheck2 = find(sum(memb2,2) == col - 1);
% Increment counts
candCounts(subCheck1) = candCounts(subCheck1) + 1;
candTailCounts(subCheck2) = candTailCounts(subCheck2) + 1;

Best Answer

Method one: one ismember call: the function ismember is going to to be slowest operation, so one simple speedup is to reduce how many times you call it: Note that a vector c will only be a member if the tail c(2:end) is a member, so you can test for the tail first, and only if the tail is a member do you need to check if the first element is also a member:
T = [1,2,3,4,5,6];
C = {[1,2],[3,4],[5,6],[7,8],[9,10]};
cntC = 0;
cntT = 0;
for k = 1:numel(C)
    if ismember(C{k}(2:end),T)
        cntT = cntT+1;
        cntC = cntC+any(C{k}(1)==T);
    end
end
Method two: Convert to a matrix: if all members of C are the same size vectors, then convert C to a matrix and perform one simple comparison using bsxfun:
M = vertcat(C{:});
U = reshape(T,1,1,[]);
X = any(bsxfun(@eq,M,U),3);
xT = all(X(:,2:end),2);
xC = xT&X(:,1);
cntT = sum(xT)
cntC = sum(xC)
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