Maybe you can use ismember. (Here I'm using ii to avoid ambiguity with the imaginary unit 1i, a.k.a., i.)
ii = 3;
A = [1 2 3 4 5];
ismember(ii,A) % ii is in A
ii = [6 7];
A = [2 4 6 8 10];
ismember(ii,A) % ii(1) is in A, ii(2) is not
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!