ACF_h - Perform the hurst exponent in respect with the AutoCorrelation method
Perform the Hurst parameter in respect with the AutoCorrelation Function (ACF) method. x is the signal with length N. ACF(k)=1/(N)*sum[k=0:N-k-1]x(k)x(k-n).
x=read('./demos/fgn',-1,1); [H,ACF]=ACF_h(x,2:25);
LMS ,