T argument to
reduce_sum is not really needed,
real reduce_sum(F f, T x, int grainsize, T1 s1, T2 s2, ...)
The data in
T could be passed as part of the extra arguments (
...). The current interface is actually cumbersome when data are not easy to represent as a single vector. For example, the data might have one integer and one real per row. The
partial_sum function doesn’t really need
end arguments provide sufficient information to evaluate the data subset.