%STATISTICAL CENTRAL MOMENTS OF IMAGE HISTOGRAM
function [v,unv]=statmoments(p,n)
Lp=length(p);
if (Lp~=256) & (lp~=65536)
    error('P must be a 256- or 65536-element vector.');
end
G=Lp-1;
p==p/sum(p); p=p(:);
z=0:G;
z=z./G;
m=z*p;
z=z-m;
v=zeros(1,n);
v(1)=m;
for j=2:n
    v(j)=(z.^j)*p;
end
if nargout > 1
   unv=zeros(1,n);
   unv=m.*G;
   for j=2:n
       unv(j)=((z*G).^j)*p;
   end
end