You have to convert the locations into linear indices first, then you can grab the correct elements in the desired linear sequence. You can use sub2ind to help you do that:
ind = sub2ind(size(c), y, x); % Get linear indices
v = c(ind); % Get the elements
Doing this thus gives:
>> v = c(ind)
v =
3 1 1
You can verify for yourself that each pair of (y,x) gives you the right element you're looking for. For example, when y = 1 and x = 6, the element retrieved is 3 and so on.
