Apply User-Defined Function to Each Data Frame Element in R (Example Code)
This page explains how to apply a user-defined function to each data frame cell in the R programming language.
Creation of Exemplifying Data
data(iris) # Loading iris data set head(iris) # Sepal.Length Sepal.Width Petal.Length Petal.Width Species # 1 5.1 3.5 1.4 0.2 setosa # 2 4.9 3.0 1.4 0.2 setosa # 3 4.7 3.2 1.3 0.2 setosa # 4 4.6 3.1 1.5 0.2 setosa # 5 5.0 3.6 1.4 0.2 setosa # 6 5.4 3.9 1.7 0.4 setosa |
data(iris) # Loading iris data set head(iris) # Sepal.Length Sepal.Width Petal.Length Petal.Width Species # 1 5.1 3.5 1.4 0.2 setosa # 2 4.9 3.0 1.4 0.2 setosa # 3 4.7 3.2 1.3 0.2 setosa # 4 4.6 3.1 1.5 0.2 setosa # 5 5.0 3.6 1.4 0.2 setosa # 6 5.4 3.9 1.7 0.4 setosa
Example: Applying Manually Defined Function to Each Data Frame Cell
iris[] <- lapply(iris, function(x) { paste("new", x) }) # Using lapply() function head(iris) # Sepal.Length Sepal.Width Petal.Length Petal.Width Species # 1 new 5.1 new 3.5 new 1.4 new 0.2 new setosa # 2 new 4.9 new 3 new 1.4 new 0.2 new setosa # 3 new 4.7 new 3.2 new 1.3 new 0.2 new setosa # 4 new 4.6 new 3.1 new 1.5 new 0.2 new setosa # 5 new 5 new 3.6 new 1.4 new 0.2 new setosa # 6 new 5.4 new 3.9 new 1.7 new 0.4 new setosa |
iris[] <- lapply(iris, function(x) { paste("new", x) }) # Using lapply() function head(iris) # Sepal.Length Sepal.Width Petal.Length Petal.Width Species # 1 new 5.1 new 3.5 new 1.4 new 0.2 new setosa # 2 new 4.9 new 3 new 1.4 new 0.2 new setosa # 3 new 4.7 new 3.2 new 1.3 new 0.2 new setosa # 4 new 4.6 new 3.1 new 1.5 new 0.2 new setosa # 5 new 5 new 3.6 new 1.4 new 0.2 new setosa # 6 new 5.4 new 3.9 new 1.7 new 0.4 new setosa
Further Resources & Related Tutorials
Please find some related R tutorials in the following list.