in src/vector_of_kll.cpp [346:353]
auto vector_of_kll_sketches<T, C>::get_num_retained() const -> Array1D<uint32_t> {
auto vals = make_ndarray<uint32_t>(d_);
auto view = vals.view();
for (uint32_t i = 0; i < d_; ++i) {
view(i) = sketches_[i].get_num_retained();
}
return vals;
}