How to Apply the aggregate() Function in R (Example Code)
In this R programming article you’ll learn how to use the aggregate function to compute descriptive statistics by group.
data(iris) # Load iris flower 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) # Load iris flower 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: Apply aggregate Function to Count by Group
aggregate(iris[ , colnames(iris) != "Species"], # Apply aggregate function in R list(iris$Species), sum) # Group.1 Sepal.Length Sepal.Width Petal.Length Petal.Width # 1 setosa 250.3 171.4 73.1 12.3 # 2 versicolor 296.8 138.5 213.0 66.3 # 3 virginica 329.4 148.7 277.6 101.3 |
aggregate(iris[ , colnames(iris) != "Species"], # Apply aggregate function in R list(iris$Species), sum) # Group.1 Sepal.Length Sepal.Width Petal.Length Petal.Width # 1 setosa 250.3 171.4 73.1 12.3 # 2 versicolor 296.8 138.5 213.0 66.3 # 3 virginica 329.4 148.7 277.6 101.3