← SASnRCreate a copy of an existing dataset

Introduction

Sometimes we need a fresh copy of a dataset to experiment on — so that our changes do not touch the original.
In SAS, the idiomatic way is a DATA step with a SET statement. In R, we simply assign the existing object to a new name.
This lesson shows the same “copy CLASS to a new dataset called new_class” task in each environment.
After running, we should have two independent objects in memory: the original class and a copy called new_class with identical contents.

Create a copy of an existing dataset

SAS (Base SAS)+

R (tidyverse)+

library(tidyverse)

class<-tribble(
~Name,~Sex,~Age,~Height,~Weight,
"Alfred","M",14,69,112.5,
"Alice","F",13,56.5,84,
"Barbara","F",13,65.3,98,
)


new_class<-class

To copy a tibble in R, we simply assign it to a new name: new_class <- class.
R’s copy-on-modify semantics mean the new name and the old name start out pointing at the same data, but as soon as we modify either one, R makes a real copy behind the scenes.
So even though it looks like a reference assignment, we never have to worry about edits leaking from one object to the other.
There is no tidyverse-specific function for copying a tibble — plain assignment is the idiomatic approach.
After running, new_class has the same rows and columns as class, and the two are independent for all future edits.

Happy learning!

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Introduction

Create a copy of an existing dataset