You should preallocate the cs cell array:

[v,x] = find(diff(a)>1); %find "jumps"
xx = [0 x length(a)];
cs = cell(length(a)+1,1);
for ii = 1:length(xx)-1
   cs{ii} = a(xx(ii)+1:xx(ii+1));
end

Style comments:

• Try to keep consistent formatting, either put spaces around all equal signs, or around none.
• Terminate statements with a semicolon to prevent your function producing output to the command window.

You should preallocate the cs cell array:

[v,x] = find(diff(a)>1); %find "jumps"
xx = [0 x length(a)];
cs = cell(length(a)+1,1);
for ii = 1:length(xx)-1
   cs{ii} = a(xx(ii)+1:xx(ii+1));
end

Style comments:

• Try to keep consistent formatting, either put spaces around all equal signs, or around none.

• Terminate statements with a semicolon to prevent your function producing output to the command window.