Environments in R

Sunny Avry

June 26th, 2019

Create a variables directly in the global environment

a <- 2
b <- 5
f <- function(x) x <- 0

Show what variables and functions are defined in the current environement

ls()

1. 'a'
2. 'b'
3. 'f'

x is not in the global environment since it is in the environment of the function f

Get the current environment

environment()

<environment: R_GlobalEnv>

Get the environment of a given variable

pryr::where('f')

<environment: R_GlobalEnv>

Set a variable in a function in global environment

g <- function(y) {z <- y + 3}
g(3)

z # z is in the scope of the function

Error in eval(expr, envir, enclos): objet 'z' introuvable
Traceback:

g <- function(y) {z <<- y + 3}
g(3)

z #now z is the global scope

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