How do I count how many times in a row a value occurs?

If I have some list, say:

A = [1 2 4 3 1 1 1 1];

How do I calculate and store *how many times in a row* each number occurs?

For example, for the value 1, I would want an output of [1, 4], since it appears one time, then when it appears again in the list it repeats four times.

Any help would be appreciated.

Answer 1

[Monica Roberts]

Probably not the fastest/cleanest but this should work. Assuming that A contains at least one value.

ind = find(A==1);
answer = [];
count = 1;
for i = 1:numel(ind)-1
    d = ind(i+1)-ind(i);
    if d == 1
        count = count+1;
    else
        answer = [answer,count];
        count = 1;
    end
end
answer = [answer,count];

Answer 2

[Torsten]

A = [1 2 4 3 1 1 1 1];
Au = unique(A);
count = arrayfun(@(i)numel(find(A==Au(i))),1:numel(Au))
output = [Au;count].'

Your question is unclear since the 1 appears 5 times in the row. If you want the maximum number of subsequent repetitions of a number or something similar, you should again formulate your question properly.