How to use summarise in combination with group_by In R Language
To apply a function to every group in the data, we need to first group the data according to the classes available. The group_by() method in the dplyr package divides the data into different segments. It has the following syntax :
Syntax: group_by(col1, col2..)
Arguments : col1, col2,.. – The columns to group the data by
In the following code snippet, the group_by method is combined with a summarise method to calculate the sum of the grouped col3 values
For Example, the value 4 appears 3 times in the col3 parameter and has been returned in the output only once.
R
# Computing the summary data %>% rowwise() %>% group_by(col3) %>% summarise(sum = sum(c(col1,col3))) |
Output:
Row wise operation in R using Dplyr
The dplyr package in R programming is used to perform simulations in the data by performing manipulations and transformations. It can be installed into the working space using the following command :
install.packages("dplyr")