In the section Access arrays in memory order, along columns, there is the final sentence
(Of course, if you just do
f.(x)then it is as fast as
fdot(x)in this example, but in many contexts it is more convenient to just sprinkle some dots in your expressions rather than defining a separate function for each vectorized operation.)
I find it a bit confusing. Given the content of the section, it seems to me that the above sentence wants to highlight that
- using the dot notation is faster in the given example, but in general it will not be the case,
- even though in general the dot notation is not the most performant approach, in several contexts it is more convenient.
Based on my guess, I proposed a PR which was rejected, on the grounds that my version deviates from the intended message. However, I didn’t get what the actual intended message is.
The last comment to the PR says that the dot notation shouldn’t be slower, but the quoted message which I tried to rephrase IMHO suggests the contrary.