Hi,
The mutate function is part of the dplyr package from the Tidyverse. This is an alternative way of writing the flow of your R code and provides a great set of tools for powerful data manipulations while enhancing the readability of your code.
It can indeed look a bit daunting at first (it was for me too), but it's very handy once you get the hang of it. Most functions from tidyverse have an R counterpart that you could use. In case of the mutate, it's just updating a specific column.
library(dplyr)
myData = data.frame(x = 1:10, y = LETTERS[1:10])
#Using plain R
myResult = myData
myResult[, "x"] = myResult[, "x"] + 1
myResult[myResult$x > 5, "y"] = "Z"
myResult
#> x y
#> 1 2 A
#> 2 3 B
#> 3 4 C
#> 4 5 D
#> 5 6 Z
#> 6 7 Z
#> 7 8 Z
#> 8 9 Z
#> 9 10 Z
#> 10 11 Z
#Using mutate from dplyr
myResult = myData %>%
mutate(x = x + 1, y = ifelse(x > 5, "Z", x))
myResult
#> x y
#> 1 2 2
#> 2 3 3
#> 3 4 4
#> 4 5 5
#> 5 6 Z
#> 6 7 Z
#> 7 8 Z
#> 8 9 Z
#> 9 10 Z
#> 10 11 Z
Created on 2020-07-30 by the reprex package (v0.3.0)
It's not very clear for me what your data looks like, as you have not provided me a reprex. A reprex consists of the minimal code and data needed to recreate the issue/question you're having. You can find instructions how to build and share one here:
So if you give a a bit more detail and code on the issue, I'll try and help you further.
PJ