clear;


S = sparse(diag(eye(5)));
idx = find(S~=0);


v = rand(5, 1);

out_us_nat = sparse_update_native(S, v);
out_us_mex = S; 
sparse_update(out_us_mex, v);

if nnz(out_us_mex ~= out_us_nat)>0
    warning('inconsistent results found in sparse_update')
else
    disp('[MEX: sparse_update] consistency check passed.');
end
