Returning multiple objects in an R function

r function
CodeGuy picture CodeGuy · Jan 20, 2012 · Viewed 222.9k times · Source

How can I return multiple objects in an R function? In Java, I would make a Class, maybe Person which has some private variables and encapsulates, maybe, height, age, etc.

But in R, I need to pass around groups of data. For example, how can I make an R function return both an list of characters and an integer?

Answer

ChadBDot picture ChadBDot · Jan 20, 2012

Unlike many other languages, R functions don't return multiple objects in the strict sense. The most general way to handle this is to return a list object. So if you have an integer foo and a vector of strings bar in your function, you could create a list that combines these items:

foo <- 12
bar <- c("a", "b", "e")
newList <- list("integer" = foo, "names" = bar)

Then return this list.

After calling your function, you can then access each of these with newList$integer or newList$names.

Other object types might work better for various purposes, but the list object is a good way to get started.

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