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GNU R

The GNU R programming language is often paired with posit's RStudio Desktop IDE and a suit of libraries (language packages) known as tidyverse (includes dplyr and ggplot2).

You can also find a web interface to Rstudio on rhea (also Remote Access).

Tutorials contains additional resources.

See R Issues for log of debugged problems.

Notes

na.action

When adding module residuals back to a dataframe, you need residuals() to return the same length as the input data.frame. use lm(na.action=na.exclude).

For example, 

d <-  data.frame(x=c(1:4,NA),y=1:5);
m <- lm(x~y,d,na.action=na.exclude);
nrow(d);              # 5
length(m$residuals);  # 4
length(residuals(m))  # 5

This avoids the error 

Error in `$<-.data.frame`(`*tmp*`, ...
  replacement has 237 rows, data has 348

MASS::select vs dplyr::select

If you load MASS after dplyr, select will be MASS::select not dplyr::select and you're likely to encounter hard-to-debug errors about unused arguments

Error in select … : unused arguments

solutions include

  1. load MASS first
  2. force select to be dplyr's version, or
  3. unload MASS if you don't need it
# load mass before dplyr to have 'select' be from dplyr
library(MASS)
library(dplyr)

# force which select (if MASS was already loaded after dplyr and overwrite the function)
select <- dplyr::select

# or unload MASS
detach("package:MASS", unload=TRUE)

# check to see
environment(select) # if "MASS", you're in for a bad time