我使用以下代码重新编码了数据框中的特定列:
ptsd_copy %>%
mutate_at(vars(AAQ_1, AAQ_4, AAQ_5, AAQ_6), funs(recode(.,
'never true' = 7,
'often untrue' = 6,
'sometimes untrue' = 5,
'undecided' = 4,
'sometimes true' = 3,
'often true' = 2,
'always true' = 1))) %>%
mutate_at(vars(AAQ_2, AAQ_3, AAQ_7, AAQ_8, AAQ_9), funs(recode (.,
'never true' = 1,
'often untrue' = 2,
'sometimes untrue' = 3,
'undecided' = 4,
'sometimes true' = 5,
'often true' = 6,
'always true' = 7)))
效果很好,但我不太了解mutate_at函数中的第二个参数。为什么我需要在funs()中包装recode()函数,为什么还要在recode中使用句点参数?我的理解是mutate_at使用vars()参数和一个函数来应用于vars内部指定的所有列。那么funs()是否不是多余的?
funs()
的使用。library(dplyr)
iris %>%
mutate_at(vars(Species), funs(recode(.,
"setosa" = 1,
"versicolor" = 2,
"virginica" = 3))) %>%
head()
#> Warning: funs() is soft deprecated as of dplyr 0.8.0
#> Please use a list of either functions or lambdas:
#>
#> # Simple named list:
#> list(mean = mean, median = median)
#>
#> # Auto named with `tibble::lst()`:
#> tibble::lst(mean, median)
#>
#> # Using lambdas
#> list(~ mean(., trim = .2), ~ median(., na.rm = TRUE))
#> This warning is displayed once per session.
#> Sepal.Length Sepal.Width Petal.Length Petal.Width Species
#> 1 5.1 3.5 1.4 0.2 1
#> 2 4.9 3.0 1.4 0.2 1
#> 3 4.7 3.2 1.3 0.2 1
#> 4 4.6 3.1 1.5 0.2 1
#> 5 5.0 3.6 1.4 0.2 1
#> 6 5.4 3.9 1.7 0.4 1