Well, you want greater-or-equal. So replace the == with >=
Also, if you want to clarify an answer to a question, please write a comment on the particular answer instead of starting a new question.
Edit, following new revelations =P
Okay, you used confusing language and did not explain your problem clearly.
There may be clever ways to do this is, but I think you would benefit most from a simple and self-explanatory loop:
overThreshold = false;
col3select = false(size(info,1), 1);
for r = 1:size(info,1)
if info(r,3) >= 520
overThreshold = true;
elseif info(r,3) <= 500
overThreshold = false;
end
col3Select(r) = overThreshold;
end
