Using the rm() Function in R
Syntax
rm(list = c("object1", "object2"), envir = .GlobalEnv)
- list: A character vector of the names of objects to remove.
- envir: The environment from which to remove objects. By default, it is the global environment (.GlobalEnv).
Basic Usage
To remove a single object:
# Create an object
x <- 42
# Remove the object
rm(x)
# Verify that the object has been removed
exists("x") # Returns FALSE
To remove multiple objects:
# Create multiple objects
a <- 10
b <- "text"
c <- 3.14
# Remove multiple objects
rm(a, b, c)
# Check if objects are removed
exists("a") # Returns FALSE
exists("b") # Returns FALSE
exists("c") # Returns FALSE
Using the list Argument
You can specify objects to remove by passing a character vector of their names to the list argument.
# Create objects
var1 <- 1
var2 <- 2
var3 <- 3
# Remove objects using a list
rm(list = c("var1", "var3"))
# Check remaining objects
exists("var1") # Returns FALSE
exists("var2") # Returns TRUE
exists("var3") # Returns FALSE
Removing All Objects
To remove all objects from the workspace, use rm() with list = ls():
# Create some objects foo <- 1 bar <- 2 # Remove all objects rm(list = ls()) # Verify that all objects are removed ls() # Returns character(0) indicating no objects left
Removing Objects from a Specific Environment
You can remove objects from a specific environment (not necessarily the global environment) by specifying the envir argument.
# Create a specific environment my_env <- new.env() my_env$var1 <- 100 my_env$var2 <- 200 # Remove an object from the specific environment rm(list = "var1", envir = my_env) # Check remaining objects in the environment ls(envir = my_env) # Returns "var2"
Practical Examples
Removing a Single Object
# Create an object
temp_data <- c(1, 2, 3)
# Remove the object
rm(temp_data)
# Verify removal
exists("temp_data") # Returns FALSE
Removing Multiple Objects
# Create objects
x <- 1
y <- 2
z <- 3
# Remove selected objects
rm(x, y)
# Check remaining objects
exists("x") # Returns FALSE
exists("y") # Returns FALSE
exists("z") # Returns TRUE
Removing All Objects
# Create objects a <- 10 b <- 20 # Remove all objects rm(list = ls()) # Check if all objects are removed ls() # Returns character(0)
Removing Objects from a Specific Environment
# Create a new environment and add objects my_env <- new.env() my_env$obj1 <- "foo" my_env$obj2 <- "bar" # Remove an object from this environment rm(list = "obj1", envir = my_env) # Check remaining objects in the environment ls(envir = my_env) # Returns "obj2"
Summary
The rm() function in R is a powerful tool for managing your workspace by removing objects that are no longer needed. You can remove one or more objects, specify objects using a character vector, and even clear all objects from the workspace. Additionally, you can target specific environments to remove objects, providing flexibility in managing different contexts within your R sessions.