How to use summarise_all() method In R Language

Method 2: Using summarise_at() method

The summarise_all method in R is used to affect every column of the data frame. The output data frame returns all the columns of the data frame where the specified function is applied over every column.

summarise_all(data, function)

Arguments :

data – The data frame to summarise the columns of
function – The function to apply on all the data frame columns.

R

library("dplyr") 
  
# creating a data frame 
df < - data.frame(col1=sample(rep(c(1: 5), each=3)), 
                  col2=5: 19) 
  
print("original dataframe") 
print(df) 
  
# summarising the data 
print("summarised dataframe") 
summarise_all(df, mean) 

Output

[1] "original dataframe"
col1 col2 
1     2    1 
2     3    2 
3     4    3 
4     2    4 
5     2    5 
6     4    6 
7     1    7 
8     1    8 
9     5    9 
10    3   10 
11    5   11 
12    1   12 
13    4   13 
14    5   14 
15    3   15    
col1 col2
 1    3    8

Explanation: The mean of all the values is calculated column-wise, that is, the sum of values of col1 is calculated and divided by the number of rows. Similarly, the summation of values is computed for col2 and col3. All the columns are returned in the final output.