A quick demo how to compute rowwise means with the tidyverse

1 Load packages

library(tidyverse)  # data wrangling

2 Motivation

Sometimes is is neccessary to compute functions, such as mean values, rowwise, ie., summing the values for multiple variables (my_vars) for each observation.

3 Minimal example

For the sake of simplicity, we’ll make use of the mtcars dataset.

data(mtcars)

my_vars <- c("mpg", "cyl", "hp")

mtcars <-
  mtcars |> 
  select(all_of(my_vars)) |> 
  rowwise() |> 
  mutate(mtcars_score = mean(c_across(all_of(my_vars)), na.rm = TRUE))

head(mtcars)  # check
#> # A tibble: 6 × 4
#> # Rowwise: 
#>     mpg   cyl    hp mtcars_score
#>   <dbl> <dbl> <dbl>        <dbl>
#> 1  21       6   110         45.7
#> 2  21       6   110         45.7
#> 3  22.8     4    93         39.9
#> 4  21.4     6   110         45.8
#> 5  18.7     8   175         67.2
#> 6  18.1     6   105         43.0

Check:

(21+6+110) / 3
#> [1] 45.66667

5 Reproducibility

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