将NA替换为特定ids的文本

Question

基于下面的代码和数据，如何将列NAs中的a替换为基于列id中的特定ids的Transportation Element Maps 2012

代码：

# Sample df
df = structure(list(id = c(1, 2, 3, 4, 5, 6, 7), a = c("a", "Transportation Element Maps 2012", NA, NA, NA, NA, NA)), class = "data.frame", row.names = c(NA, 
-7L))

# Desired df
df1 = structure(list(id = c(1, 2, 3, 4, 5, 6, 7), a = c("a", "Transportation Element Maps 2012", "Transportation Element Maps 2012", "Transportation Element Maps 2012", "Transportation Element Maps 2012", "Transportation Element Maps 2012", NA)), class = "data.frame", row.names = c(NA, 
-7L))

# Current approach which throws an error
df1 = df %>% ifelse(id %in% 3:6) %>%  mutate(a %in% NA, "Transportation Element Maps 2012")

# Error
Error in ifelse(., reference_number %in% 3:6) : 
  'list' object cannot be coerced to type 'logical'

Answer 1

使用is.na查找返回逻辑向量的NA元素，并将id %in% 3:6保存在mutate中。

library(dplyr)
df %>% 
  mutate(a = ifelse(id %in% 3:6 & is.na(a), 
      "Transportation Element Maps 2012", a))

Answer 2

您可以使用replace函数，并使用c将3:6和NA组合在一起，如下所示：

library(dplyr)

df |> 
  mutate(a = replace(a, id %in% c(3:6, NA), "Transportation Element Maps 2012"))