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+14

Back arrow vs front arrow in R

When should I use the front arrow vs the back arrow for assignments ? -> vs <-

4/9/2021 2:27:26 AM

ChillPill 🌶

5 Answers

New Answer

+17

Here's something you might find interesting 👇 https://stackoverflow.com/questions/51547389/why-are-there-two-assignment-operators-and-in-r

+6

Not a direct answer, but: Doing data preparation and analysis in R, I have never used (or needed) "->" Concerning scripts (not directly typed to console code): I think our instructor used to tell us, he considered "->" bad style or something alike... (it's some time ago, I might be mistaken) edit: R also allows using "=" x = 1 but 2 = y # error edit 2: x <<- 1

+5

Arsenic thanks i tried what one comment said about magrittr. front arrows seem to keep the flow as promised https://code.sololearn.com/c5GjQ3WkvQ5I/?ref=app

0

-> is considered bad practice, but there's also two others. = Is instanced <<- is global So, > mean(x = 1:5) > x Will return [1] 3 [1] Error: object "x" not found because x is only defined for that single run of the code Next, > mean(x <- 1:5) > x Will return [1] 3 [1] 1 2 3 4 5 Because after the code is ran, it assigns every number from 1 to 5 inside a variable called x Last, > foo <- function() { > bar <- 5 > bar > } > foo() > bar Will return [1] 5 [1] Error: object "bar" not found Because it only assigned bar with a value of 5 inside the function But > foo <- function() { > bar <<- 5 > bar > } > foo() > bar Will return [1] 5 [1] 5 Because it assigned the bar variable outside of the function as 5