% create a vector with a random numbers
x = rand(1000000, 1);

fprintf('time needed to manually filter elements smaller than 0.5 in a vector of length %i\n', length(x))

tic
results = [];
matches = 1;
for i = 1:length(x)
    if x(i) < 0.5
        results(matches) = x(i);
        matches = matches + 1;
    end
end
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fprintf('\ntime needed to do the same with logical indexing\n')

tic
results = x(x < 0.5);
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