r - 如何使用 R 中前几行的示例数据填充非相邻行？

Question

我有包含唯一标识符、类别和描述的数据。下面是一个玩具数据集。

prjnumber <- c(1,2,3,4,5,6,7,8,9,10)
category <- c("based","trill","lit","cold",NA,"epic", NA,NA,NA,NA)
description <- c("skip class",
                 "dunk on brayden",
                 "record deal",
                 "fame and fortune",
                 NA,
                 "female attention",
                 NA,NA,NA,NA)
toy.df <- data.frame(prjnumber, category, description)

> toy.df
       prjnumber category      description
    1          1    based       skip class
    2          2    trill  dunk on brayden
    3          3      lit      record deal
    4          4     cold fame and fortune
    5          5     <NA>             <NA>
    6          6     epic female attention
    7          7     <NA>             <NA>
    8          8     <NA>             <NA>
    9          9     <NA>             <NA>
    10        10     <NA>             <NA>

我想从已填充的行中随机抽取“类别”和“描述”列，以用作具有缺失数据的行的填充。最终的数据框将是完整的，并且只依赖于包含数据的前 5 行。该解决方案将保留列间相关性。预期输出为:

> toy.df
       prjnumber category      description
    1          1    based       skip class
    2          2    trill  dunk on brayden
    3          3      lit      record deal
    4          4     cold fame and fortune
    5          5      lit      record deal
    6          6     epic female attention
    7          7    based       skip class
    8          8    based       skip class
    9          9     lit       record deal
    10        10   trill   dunk on brayden

Answer 1

complete = na.omit(toy.df)
toy.df[is.na(toy.df$category), c("category", "description")] =
    complete[sample(1:nrow(complete), size = sum(is.na(toy.df$category)), replace = TRUE),
             c("category", "description")]
toy.df
#    prjnumber category      description
# 1          1    based       skip class
# 2          2    trill  dunk on brayden
# 3          3      lit      record deal
# 4          4     cold fame and fortune
# 5          5      lit      record deal
# 6          6     epic female attention
# 7          7     cold fame and fortune
# 8          8    based       skip class
# 9          9     epic female attention
# 10        10     epic female attention

虽然如果您不从为 NA 行填写的唯一标识符开始，看起来会更直接一些...