samer@4: function X=diffdims(X,Dims)
samer@4: % diffdims - diff along multiple dimensions
samer@4: %
samer@4: % diffdims :: 
samer@4: %    [D:[[1,E]->natural]]  ~'E dimensional array of size D', 
samer@4: %    [[K]->[E]]            ~'K dimensions each from 1 to E'
samer@4: % -> [DD].                 ~'array of diffs, smaller by one in each diffed dim'.
samer@4: 
samer@4: for d=Dims, X=diff(X,1,d); end