3 surprising facts about the computation of scalar products by Daniel Lemire.
From the post:
The speed of many algorithms depends on how quickly you can multiply matrices or compute distances. In turn, these computations depend on the scalar product. Given two arrays such as (1,2) and (5,3), the scalar product is the sum of products 1 × 5 + 2 × 3. We have strong incentives to compute the scalar product as quickly as possible.
Sorry, can’t tell you the three things because that would ruin the surprise. 😉 See Daniel’s blog for the details.