The R language, for programmers

r-languageprogrammingstatistical-computingdata-typesvectors

Abstraction: R language quirks and idioms explained for experienced programmers

Key points:

R should be understood as a statistical environment that has a programming language (like VBA for Excel), not as a general-purpose language
Primary data type is the vector (1-indexed, FORTRAN column-major order); no scalar type — single numbers are length-1 vectors; shorter vectors are recycled when added to longer ones
Assignment uses <-; dot used as name separator (no OOP meaning); $ accesses named list elements (analogous to dot in other languages); T/F are reassignable variables, not reserved keywords — use TRUE/FALSE
NA (not applicable, missing data) is distinct from NaN; is.na() returns TRUE for both; functions must handle NA in any vector argument
Negative indices return a copy of the vector with that element removed (not Python-style reverse indexing)
Distribution functions follow d/p/q/r prefix convention: density, CDF, quantile, random sample (e.g., dnorm, rnorm)

Connections: R Programming · Statistical Computing