This has nothing to do with understanding backpropagation (which (correct me if i m wrong) is really the core of DL). In fact in the old days backpropagation wa

This has nothing to do with understanding backpropagation (which (correct me if i m wrong) is really the core of DL). In fact in the old days backpropagation was all about "propagating the deltas" and nothing about vectorizing.