Confidence bounds using the function cdf in matlab

Hello,

I want to get as an output the confidence bounds 'flo' and 'fup' along with the cumulative distribution function 'f' using the function cdf only. the description of this function tells you that you can only get f as an output. However, I have tried it and it actually gives you fup and flo, which brings me to my question: I think that the alpha used by default is 0.05 and I want to know how to change it in the cdf function. Can you tell me how to do that or at least can you give me the hole description of the cdf function?

Thanks :-).