Coding Guidelines and Style

Generally, we follow Hadley Wickham's R style guide.

Most importantly:

• Use <- for assignment, not =.
• Operators do get spacing, parentheses do not: if (x + 1) print("yes")
• Use short, clear, and consistent variable names.
• Clearly comment your code and data.

Standard R packages

We're using a standard set of R packages to handle many tasks–mostly from what is known as the tidyverse. These include:

• dplyr for data manipulation and processing;
• tidyr for data reshaping;
• assertthat for assertions;
• tibble for better data frames;
• magrittr for building pipelines.

Pipelines

A word about pipelines: we aim to use these consistently and when it makes sense...but don't take things to extremes. Sometimes y <- f(g(x)) really is the clearest notation.

Things NOT to use

The package tests will raise an error for all of these:

• R's match() function
• The reshape or reshape2 packages (i.e. melt or cast)
• Loops (this is not an ironclad prohibition, but should be very rare)
• R's ifelse function - if necessary use dplyr::if_else instead
• Any of R's apply family of functions, rowMeans, etc. (again, with rare exceptions)
• Successive mutate() calls. See Hints for speed