Computation method is different

[klukonin]

Why computation is different?

In the original article computation formula is

power(i) = noise_floor + RSSI + 10 * log(b(i)^2) - 10 * log(sum[i=1..56](b(i)^2)

But in ath_spectral you use another one

power(i) = noise_floor + RSSI + 20 * log10(b(i)^2) - 10 * log10(sum[i=1..56](b(i)^2)

SO... I'm a little bit frustrated. log10() instead of log() and multiplication by 20 instead of 10.
Could you please explain this another computation method?