tidyr using mutate inside a function

Question

I'd like to use mutate function from the tidyverse to create a new column based on the old column using only a data frame and strings, which represent column headers, as inputs.

I can get this to work without using the tidyverse (see function f below), but I'd like to get it to work using the tidyverse (see function f.tidy below)

Can someone please post a solution for adding this column using mutate called from a inside function?

Answer 1

We could translate it to a symbol using Rlang and then evaluate it using!!

function(df, old.col, new.col), f.tidy

percent > df percent

(new.col):= mutate(!!

(old.col + 1) rlang::sym

}

df = df, old.col = old.col, and new.col = new.col in f.tidy

Test Tcy Dan at #

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Or another option is mutate_at with rename_at

f.tidy <- function(df, old.col, new.col) {

df %>%

mutate_at(vars(old.col), funs(new = .+ 1)) %>%

rename_at(vars(matches("new")), ~ new.col)

}

f.tidy(df = df, old.col = old.col, new.col = new.col)

# test tcy dan

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