与NA匹配的值-缺少值-使用mutate [英] Value matching with NA - missing values - using mutate

问题描述

我有些困惑。是否有比下面更好的方法来进行值匹配，将NA视为 mutate 内的真实值？

I am somewhat stuck. Is there a better way than the below to do value matching considering NAs as "real values" within mutate?

library(dplyr)

data_foo <- data.frame(A= c(1:2, NA, 4, NA), B = c(1, 3, NA, NA, 4))

不是所需的输出：

data_foo %>% mutate(irr = A==B)

#>    A  B   irr
#> 1  1  1  TRUE
#> 2  2  3 FALSE
#> 3 NA NA    NA
#> 4  4 NA    NA
#> 5 NA  4    NA

data_foo %>% rowwise() %>% mutate(irr = A%in%B)

#> Source: local data frame [5 x 3]
#> Groups: <by row>
#> 
#> # A tibble: 5 x 3
#>       A     B irr  
#>   <dbl> <dbl> <lgl>
#> 1     1     1 TRUE 
#> 2     2     3 FALSE
#> 3    NA    NA FALSE
#> 4     4    NA FALSE
#> 5    NA     4 FALSE

所需的输出：下面显示了所需的列， irr 。我正在使用这种麻烦的辅助专栏。有更短的方法吗？

Desired output: The below shows the desired column, irr. I am using this somewhat cumbersome helper columns. Is there a shorter way?

data_foo %>% 
  mutate(NA_A = is.na(A), 
         NA_B = is.na(B), 
         irr = if_else(is.na(A)|is.na(B), NA_A == NA_B, A == B))

#>    A  B  NA_A  NA_B   irr
#> 1  1  1 FALSE FALSE  TRUE
#> 2  2  3 FALSE FALSE FALSE
#> 3 NA NA  TRUE  TRUE  TRUE
#> 4  4 NA FALSE  TRUE FALSE
#> 5 NA  4  TRUE FALSE FALSE

推荐答案

也许比 akrun的答案？

以下两种方式中的任何一种都会产生预期的结果。请注意， as.character 不会这样做，因为 as.character（NA）的返回值为 NA_character _ 。

Maybe simpler than akrun's answer?
Any of the two ways below will produce the expected result. Note that as.character won't do it, because the return value of as.character(NA) is NA_character_.

data_foo %>%
  mutate(irr = paste(A) == paste(B))

data_foo %>%
  mutate(irr = sQuote(A) == sQuote(B))

#Source: local data frame [5 x 3]
#Groups: <by row>
#
## A tibble: 5 x 3
#      A     B irr  
#  <dbl> <dbl> <lgl>
#1     1     1 TRUE 
#2     2     3 FALSE
#3    NA    NA TRUE 
#4     4    NA FALSE
#5    NA     4 FALSE

编辑。

1. 在下面的注释之后，我更新了代码，现在它遵循akrun的建议。


2. 在 tmfmnk的答案。我使用另一种类似的方法来解决问题的问题。

1. Following the comments below I have updated the code and it now follows akrun's suggestion.
2. There is also the excellent idea in tmfmnk's answer. I use a similar one in yet another way of solving the question's problem.

all.equal的文档表示

请勿使用 all.equal 直接在 if 表达式中使用
isTRUE（all.equal（....））或相同（如果适用）。

Do not use all.equal directly in if expressions—either use isTRUE(all.equal(....)) or identical if appropriate.

尽管没有如果 mutate 中的if 表达式，我相信它比相同更稳定，并且具有如果所比较的值相等（实际上），则效果相同。

Though there is no if expression in mutate, I believe that it is more stable than identical and has the same effect if the values being compared are (sort of/in fact) equal.

data_foo %>%
  mutate(irr = isTRUE(all.equal(A, B)))

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