samer@4: function b=pad(x,sz,a), 
samer@4: % pad - pad out an array to given size with given elements
samer@4: %
samer@4: % pad :: A, D:[[2]], [[S]->A] -> [D->A].
samer@4: 
samer@4: [N,M]=size(a);
samer@4: b=repmat_to(x,max(sz,[N,M]));
samer@4: b(1:N,1:M)=a;