code vs written formula

I am trying to understand what calxculation the code is doing.. can you breakdown the formuola in the first line like how it looks when written in mathematical form?

Nfft = 2^(ceil(log2(size(freq,2)))+1);
Ts = 1/Nfft/(freq(2)-freq(1)+1e-16); %Avoid nan checks
time_vec = (0:Ts:Ts*(Nfft-1));
dist_vec = time_vec*1.5e8; %distance in meters

[Torsten]

Take the number of columns of the matrix "freq", take the log to the basis 2 of this number, take the nearest positive integer (>= this number), take (2^this number) and multiply the result by 2.

E.g. if freq has 64 columns, you get 64 = 2^6 -> 6 -> 6 -> 2^6 = 64 -> 2*64=128 = Nfft.