Counting the number of runs in a sequence

I have a sequence made up a number of 1's and 0's and I want to count how many runs of numbers occur within the sequence. For example taken the matrix

A=[1,1,1,0,0,1,1,1,1,0,0,0,0,1]

The 1st run: 1,1,1 The 2nd run: 0,0 The 3rd run: 1,1,1,1 The 4th run: 0,0,0,0 The 5th run: 1,

Therefore the total number of runs is 5.

Any help would be much appreciated thanks

Answer 1

[Matt J]

 N_runs=nnz(diff(A))+1;

Answer 2

[Azzi Abdelmalek]

numel(strfind(A,[0,1]))+ numel(strfind(A,[1,0]))+1

Answer 3

[Jan]

See http://www.mathworks.com/matlabcentral/fileexchange/41813-runlength:

N_runs = length(RunLength(A));

Answer 4

[David Sanchez]

A=[1,1,1,0,0,1,1,1,1,0,0,0,0,1];

N_runs = 1;
for k=2:length(A)
    if A(k)~=A(k-1)
        N_runs = N_runs +1;
    end
end

[Jan]

Vectorized:

N_runs = sum(A(2:end) ~= A(1:end-1));

Answer 5

[Matt J]

If you have the Image Processing Toolbox,

 C=bwconncomp([A,~A]); 
 N_runs=C.NumObjects;