r - 将变量传递给 tidyr::pivot_wider 的 names_glue 参数

Question

以下是一些我们使用两个名称进行更广泛旋转的愚蠢数据:

library(tidyr)

df <- data.frame(
    food = c('banana','banana','banana','banana','cheese','cheese','cheese','cheese'),
    binary = c(rep(c('yes','no'), 4)),
    car = c('toyota','subaru','mazda','skoda','toyota','subaru','mazda','skoda'),
    fun = c(2,4,3,6,2,4,2,3))

df %>%
    pivot_wider(
        id_cols = food,
        names_from = c(car, binary),
        values_from = fun)

如果我们想改变新变量名的格式，例如从 toyota_yes至 yes_toyota ，我们使用 names_glue争论:

df %>%
    pivot_wider(
        id_cols = food,
        names_from = c(car, binary),
        names_glue = "{binary}_{car}",
        values_from = fun)

我面临的问题是找到将变量名传递给 names_glue 的正确语法。范围。将变量传递给 names_from 很容易，例如:

var1 <- 'car'
var2 <- 'binary'
df %>%
    pivot_wider(
        id_cols = food,
        names_from = c(var1, var2),
        values_from = fun)

但是我们不能直接用 names_glue 做到这一点。 :

df %>%
    pivot_wider(
        id_cols = food,
        names_from = c(var1, var2),
        names_glue = "{var1}_{var2}",
        values_from = fun)

Error: Column names car_binary, car_binary, and car_binary must not be duplicated.

据推测，它正在评估变量并将结果字符串(即“汽车”或“二进制”)传递给胶水函数。我玩过一些我通常会用于整洁评估的东西( !!sym(...) 等)，但没有任何工作。所需的输出如下，使用 names_glue 的变量范围:

# A tibble: 2 x 5
  food   yes_toyota no_subaru yes_mazda no_skoda
  <fct>       <dbl>     <dbl>     <dbl>    <dbl>
1 banana          2         4         3        6
2 cheese          2         4         2        3

Here is the commit that added the names_glue parameter to pivot_wider -- although I can't really figure out how to troubleshoot with this.

Answer 1

您可以使用 sprtinf/paste0构造字符串:

library(tidyr)
df %>%
  pivot_wider(
    id_cols = food,
    names_from = c(var1, var2),
    names_glue = sprintf('{%s}_{%s}', var2, var1),
    values_from = fun)

#  food   yes_toyota no_subaru yes_mazda no_skoda
#  <chr>       <dbl>     <dbl>     <dbl>    <dbl>
#1 banana          2         4         3        6
#2 cheese          2         4         2        3