Count consecutive elements in an array

suppose i have an array like: A = [1 1 1 1 2 2 2 4 4 4 4 1 1 1 1 2]

I want the result in this form, B = [4 3 4 4 1].

or something like this will be best: B = [4 1; 3 2; 4 4; 4 1; 1 2]. First colums contains the number of entry and the second colums contains the entry itself.

Kindly help.

Answer 1

[Mathieu NOE]

hello

try this :

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

%% main code
p=find(diff(A)~=0);
s1 = [p(1) diff(p) numel(A)-p(end)];
s2 = A(cumsum(s1));
B = [s1' s2'] % First colums contains the number of entry and the second colums contains the entry itself

[Debraj Midya]

This worked. Thank you Sir.

[Mathieu NOE]

my pleasure