Matlab: finding change points in cell array

Question

If I have a cell array

CELLS = {'AB','AB','AB','BC','BC','CD','CD','CD','DF','FG'}

How do I find the indices of the locations at which the elements change?

in this example I'm looking for an output like:

score 3 · Accepted Answer · answered Aug 02 '13 at 18:39

3

For a generic cell array of string call unique(), and find(diff(...)) the position index:

s = {'AB','AB','AB','BC','BC','CD','CD','CD','DF','FG'};
[~,~,p] = unique(s)
find(diff(p)==1)+1

answered Aug 02 '13 at 18:39

Oleg

score 2 · Answer 2 · answered Aug 02 '13 at 18:20

2

This will do:

CHANGES = find(diff(cell2mat(CELLS)))+1

answered Aug 02 '13 at 18:20

Luis Mendo

I accidentally oversimplified my question a bit: what if `CELLS = {'AB','AB','AB','BC','BC','CD','CD','CD','DF','FG'}`? – siegel Aug 02 '13 at 18:27

2 Answers2