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  • Relative frequencies proportions with dplyr - Stack Overflow
    dplyr 0 7 1: returns an ungrouped table: you need to group again by am dplyr < 0 7 1: returns a grouped table, so no need to group again, although you might want to ungroup() for later manipulations
  • Can dplyr join on multiple columns or composite key?
    I realize that dplyr v3 0 allows you to join on different variables: left_join(x, y, by = c("a" = "b") will match x a to y b However, is it possible to join on a combination of variables or do I have to add a composite key beforehand? Something like this: left_join(x, y, by = c("a c" = "b d") to match the concatenation of [x a and x c] to [y b
  • dplyr: conditional column selection using select_if ()
    Thank you @divibisan, this is very helpful I realized (see comment above) that I was asking the wrong question, as what I really wanted is for the "count" column to not be included in the mutate_all() call (because I need the counts but 100 is the result of count count *100
  • How to use or and in dplyr to subset a data. frame
    Interesting I was trying to see the difference in terms of the resulting dataset and I coulnd't get an explanation to why the good old "[" operator behaved differently:
  • r - Find duplicated elements with dplyr - Stack Overflow
    Newer versions of dplyr you can use only filter together with the by argument without having to use group_by: mtcars |> filter(n() > 1, by = carb) This has the advantage of not having to do any ungroup after


















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