By Matt Brousil
This week I'm going to walk through some examples of applying functions to every item in one (or more) lists. Basically this gives an overview answering the question: "If I have a list of data, how do I loop through that list manipulating and running analyses on its data without using for() …
By Julia Piaskowski
Sources Thomas Lumley, Github repo useRfasteR Hadley Wickham, Profiling, Advanced R Dirk Eddelbuettel, Rcpp
The Process for Improving Code: (quote from Advanced R)
Find the biggest bottleneck (the slowest part of your code).
Try to eliminate it (you may not succeed but that's ok).