How to Use aggregate Function in R

In this article, we will discuss how to use aggregate function in R Programming Language.

aggregate() function is used to get the summary statistics of the data by group. The statistics include mean, min, sum. max etc.

Syntax:

aggregate(dataframe$aggregate_column, list(dataframe$group_column), FUN) 

where

• dataframe is the input dataframe.
• aggregate_column is the column to be aggregated in the dataframe.
• group_column is the column to be grouped with FUN.
• FUN represents sum/mean/min/ max.

Example 1: R program to create with 4 columns and group with subjects and get the aggregates like minimum, sum, and maximum.

R

# create a dataframe with 4 columns
data = data.frame(subjects=c("java", "python", "java",
                             "java", "php", "php"),
                  id=c(1, 2, 3, 4, 5, 6),
                  names=c("manoj", "sai", "mounika",
                          "durga", "deepika", "roshan"),
                  marks=c(89, 89, 76, 89, 90, 67))

# display
print(data)

# aggregate sum of marks with subjects
print(aggregate(data$marks, list(data$subjects), FUN=sum))

# aggregate minimum  of marks with subjects
print(aggregate(data$marks, list(data$subjects), FUN=min))

# aggregate maximum of marks with subjects
print(aggregate(data$marks, list(data$subjects), FUN=max))

Output:

Example 2: R program to create with 4 columns and group with subjects and get the average (mean).

R

# create a dataframe with 4 columns
data = data.frame(subjects=c("java", "python", "java",
                             "java", "php", "php"),
                  id=c(1, 2, 3, 4, 5, 6),
                  names=c("manoj", "sai", "mounika",
                          "durga", "deepika", "roshan"),
                  marks=c(89, 89, 76, 89, 90, 67))

# display
print(data)

# aggregate average of marks with subjects
print(aggregate(data$marks, list(data$subjects), FUN=mean))

Output: