When converting daily volatilities to annual volatilities one need to multiply with $\sqrt{252}$.
But I found this piece of code this piece of code who calculate log-returns in the following way: In MATLAB:
y=price2ret(CrixData(:,2))*sqrt(250);
The documentation for price2ret
function is given here, and what this function does is calculating returns of historical data. Why does one also need to multiply with $\sqrt{252}$ in this case?