matlab - Finding the # of sequences in an array -

matlab - Finding the # of sequences in an array -

i need study # of sequences in array. example:

a=[ 1 1 -1 -1 -1 -1 -1 0 1 -1 -1 -1 -1 1 1 -1 -1 1 0 1 1]

and have study # of times number comes consecutively, such as, 1 sequence of

5 -1s ([-1 -1 -1 -1 -1]) , 1 sequence of

4 -1s ([-1 -1 -1 -1]).

how can find how many sequences of numbers there are?

you may utilize run-length encoding perform task

function [rl data] = runlength( vec ) % run length encoding vector vec rl = ( find( vec ~= [vec(2:end), vec(end)+1] ) ); info = vec( rl ); rl(2:end) = rl(2:end) - rl(1:end-1);

applying run-length encoding a

>> [rl data] = runlength( ) rl = [ 2 5 1 1 4 2 2 1 1 2 ] info = [ 1 -1 0 1 -1 1 -1 1 0 1 ]

so, if interested in number of sequences of length > n need is

>> nnz( rl > n )

matlab numbers sequences