Need help writing expression in regexp!!!

So I have the following lines of code:

cardelem=find(~cellfun(@isempty, regexpi(Lines, '^C(?!ORD)', 'match')));
cardprop=find(~cellfun(@isempty, regexpi(Lines, '^P(?!LOAD)', 'match')));
cardmats=find(~cellfun(@isempty, regexpi(Lines, '^MAT(?!T)', 'match')));
cardcs=find(~cellfun(@isempty, regexpi(Lines, '^CORD', 'match')));

how do I write the expression for another regexpi function that includes everything that was NOT included in the expressions above? OR should I use the indices I found above to find indices in Lines that were not included above- how would I got about doing that if it's easier? I basically want to find the locations of "other".

Right now all I can think of doing is [^*CP] and something else maybe - I dont even know if that's going in the right direction.

Answer 1

[Kelly Kearney]

idx = setdiff(1:length(Lines), [cardelm; cardprop; cardmats; cardcs]);

[Megna Hari]

Thank you Kelly!!! I didn't even know something like setdiff existed!