% diffsum1.m
% compute differential sum along a given dimension

x = cat(3,hankel([3 1 6 -1]),pascal(4)) % data to test
dim=1  % dimension to work along

xsiz=size(x)
xdim=ndims(x)

tmp=repmat({':'},1,xdim) % cells of ':'
c1=tmp;
c1{dim}=1:xsiz(dim)-1    % poke in 1:end-1
c2=tmp;
c2(dim)={2:xsiz(dim)}    % poke in 2:end

y=x(c1{:})+x(c2{:})