Calculate cumsum by Groups of Data Frame in R (Example Code)

This article explains how to compute the cumsum by groups in a data frame in the R programming language.

Construction of Example Data

data(iris)                         # Load example data
iris_sub <- iris[c(1, 2, 51, 52, 101, 102), ]
iris_sub
#     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
# 51           7.0         3.2          4.7         1.4 versicolor
# 52           6.4         3.2          4.5         1.5 versicolor
# 101          6.3         3.3          6.0         2.5  virginica
# 102          5.8         2.7          5.1         1.9  virginica

Example: Calculate Cumulative Sum by Group Using group_by & mutate Functions of dplyr Package

install.packages("dplyr")          # Install & load dplyr
library("dplyr")
iris_cumsum <- iris_sub %>%        # Create cumsum column
  group_by(Species) %>%
  dplyr::mutate(SL_cs = cumsum(Sepal.Length))
head(iris_cumsum)
                 # # A tibble: 6 × 6
# # Groups:   Species [3]
#   Sepal.Length Sepal.Width Petal.Length Petal.Width Species    SL_cs
#          <dbl>       <dbl>        <dbl>       <dbl> <fct>      <dbl>
# 1          5.1         3.5          1.4         0.2 setosa       5.1
# 2          4.9         3            1.4         0.2 setosa      10  
# 3          7           3.2          4.7         1.4 versicolor   7  
# 4          6.4         3.2          4.5         1.5 versicolor  13.4
# 5          6.3         3.3          6           2.5 virginica    6.3
# 6          5.8         2.7          5.1         1.9 virginica   12.1

Leave a Reply

Your email address will not be published.

Fill out this field
Fill out this field
Please enter a valid email address.
You need to agree with the terms to proceed

Menu
Top