datareplace.m

计算Detrended Fluctuation Exponent(DFA)指数

function P=DataReplace(data,j)
if j==1
    n=0;
    while  data(j+n)==0
        n=n+1;
    end
    P=data(j+n);
elseif j==length(data)
    m=0;
    while  data(j-m)==0
        m=m+1;
    end
    P=data(j-m);
else
    n=0;m=0;
    while  (data(j+n)==0)&(j+n<length(data))
        n=n+1;
    end
    while  data(j-m)==0
        m=m+1;
    end
    P=(data(j+n)+data(j-m))/2;
end