How to store values as array

How do you store all k values as a single array?

    for ii = nn 
       k = ((-1).^(ii-1)).*((xx^(2.*(ii-1))))./(factorial(2.*(ii-1)));
    end

Answer 1

[per isakson]

There are a couple of mistakes in your code. Try this

k = nan( 1, nn ); % pre-alloctate memory
for ii = 1 : nn 
    k(ii) = ((-1).^(ii-1)).*((xx^(2.*(ii-1))))./(factorial(2.*(ii-1)));
end
assert( all(not(isnan(k))) )