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从嵌套列表中提取数据并返回data.frame

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dput(head(z2,10))

structure(list(name = list("Mary"), department = structure(list(
    name = list("English")), .Names = "name", id = "300"), department = structure(list(
    name = list("Math")), .Names = "name", id = "301"), 
    department = structure(list(name = list("Chinese")), .Names = "name", id = "302f"), 
    department = structure(list(name = list("German")), .Names = "name", id = "302"), 
    department = structure(list(name = list("German")), .Names = "name", id = "302f"), 
    department = structure(list(name = list("Music")), .Names = "name", id = "303"), 
    department = structure(list(name = list("Sport")), .Names = "name", id = "305"), 
    department = structure(list(name = list("Chemistry")), .Names = "name", id = "306"), 
    department = structure(list(name = list("Science")), .Names = "name", id = "308")), .Names = c("name", 
"department", "department", "department", "department", "department", "department", 
"department", "department", "department"))

我试图从列表中提取信息并将其放入data.frame，从my previous post，我刚刚了解到你可以使用 do.call 函数对其进行格式化，我想将其作为数据框输出 .

这是该帖子中answer的代码：

c <- do.call(rbind,             
        lapply(unname(z2), 
               function(x) { 
                 temp <- unlist(x) 
                 data.frame(names(temp) == "name",
                            temp[names(temp) == "department.name"], 
                            unlist(sapply(x, attr, "id")), 
                            row.names=NULL) 
               }))

data.frame（names（temp）==“name”中的错误，temp [names（temp）==“department.name”]，：参数意味着不同的行数：1,0

新数据：

structure(list(code = list("1"), note = list("success"), category = structure(list(
    name = list("Mary"), department = structure(list(name = list(
        "Math")), .Names = "name", id = "300"), department = structure(list(
        name = list("English")), .Names = "name", id = "301"), 
    department = structure(list(name = list("Chinese")), .Names = "name", id = "302f"), 
    department = structure(list(name = list("Music")), .Names = "name", id = "317")), .Names = c("name", 
"department", "department", "department", "department", "department", "department", 
"department", "department", "department", "department", "department", "department", 
"department", "department", "department")), category = structure(list(
    name = list("Kevin"), department = structure(list(name = list(
        "Physics")), .Names = "name", id = "12G0"), department = structure(list(
        name = list("German")), .Names = "name", id = "321"), 
    department = structure(list(name = list("French")), .Names = "name", id = "325"), 
    department = structure(list(name = list("Spanish")), .Names = "name", id = "427")), .Names = c("name", 
"department", "department", "department", "department", "department", "department", 
"department", "department", "department", "department")), category = structure(list(
    name = list("Andy"), department = structure(list(name = list(
        "Swedish")), .Names = "name", id = "330"), department = structure(list(
        name = list("Danish")), .Names = "name", id = "331"), 
    department = structure(list(name = list("Russian")), .Names = "name", id = "332"), 
    department = structure(list(name = list("Japanese")), .Names = "name", id = "341")), .Names = c("name", 
"department", "department", "department", "department", "department", "department", 
"department", "department", "department", "department", "department", "department", 
"department", "department", "department", "department", "department", "department", 
"department", "department", "department")), category = structure(list(
    name = list("Nana"), department = structure(list(name = list(
        "Arabic")), .Names = "name", id = "200"), department = structure(list(
        name = list("African")), .Names = "name", id = "201"), 
    department = structure(list(name = list("Sport")), .Names = "name", id = "202"), 
    department = structure(list(name = list("Korean")), .Names = "name", id = "211")), .Names = c("name", 
"department", "department", "department", "department", "department", "department", 
"department")), category = structure(list(name = list("Sandy"), 
    department = structure(list(name = list("Vocals")), .Names = "name", id = "100"), 
    department = structure(list(name = list("Language")), .Names = "name", id = "515")), .Names = c("name", 
"department", "department", "department", "department", "department", "department", 
"department", "department", "department", "department", "department", "department"
))), .Names = c("code", "note", "category", "category", "category", 
"category", "category"))
r dataframe lapply sapply do.call

1 回答

  • 3

    基于OP的新样本和嵌套列表编辑的答案，每个表示一个用户（下面复制的数据集的修改版本，因为每个类别中的名称多于元素，这没有多大意义） .

    数据：

    z2 <- structure(list(code = list("1"), 
                     note = list("success"), 
                     category = structure(list(name = list("Mary"), 
                                               department = structure(list(name = list("Math")), .Names = "name", id = "300"), 
                                               department = structure(list(name = list("English")), .Names = "name", id = "301"), 
                                               department = structure(list(name = list("Chinese")), .Names = "name", id = "302f"), 
                                               department = structure(list(name = list("Music")), .Names = "name", id = "317")), 
                                          .Names = c("name", "department", "department", "department", "department")), 
                     category = structure(list(name = list("Kevin"), 
                                               department = structure(list(name = list("Physics")), .Names = "name", id = "12G0"), 
                                               department = structure(list(name = list("German")), .Names = "name", id = "321"), 
                                               department = structure(list(name = list("French")), .Names = "name", id = "325"), 
                                               department = structure(list(name = list("Spanish")), .Names = "name", id = "427")), 
                                          .Names = c("name", "department", "department", "department", "department")), 
                     category = structure(list(name = list("Andy"), 
                                               department = structure(list(name = list("Swedish")), .Names = "name", id = "330"), 
                                               department = structure(list(name = list("Danish")), .Names = "name", id = "331"), 
                                               department = structure(list(name = list("Russian")), .Names = "name", id = "332"), 
                                               department = structure(list(name = list("Japanese")), .Names = "name", id = "341")), 
                                          .Names = c("name", "department", "department", "department", "department")), 
                     category = structure(list(name = list("Nana"), 
                                               department = structure(list(name = list("Arabic")), .Names = "name", id = "200"), 
                                               department = structure(list(name = list("African")), .Names = "name", id = "201"), 
                                               department = structure(list(name = list("Sport")), .Names = "name", id = "202"), 
                                               department = structure(list(name = list("Korean")), .Names = "name", id = "211")), 
                                          .Names = c("name", "department", "department", "department", "department")), 
                     category = structure(list(name = list("Sandy"), 
                                               department = structure(list(name = list("Vocals")), .Names = "name", id = "100"), 
                                               department = structure(list(name = list("Language")), .Names = "name", id = "515")), 
                                          .Names = c("name", "department", "department"))), 
                .Names = c("code", "note", "category", "category", "category", "category", "category"))

    从列表中删除不需要的元素：

    # keep only category elements (i.e. drop code, note, etc. from the list)
z2 <- z2[which(names(z2)=="category")]

    将每个嵌套列表转换为数据框并将它们绑定在一起：

    do.call(rbind,
        lapply(unname(z2),
               function(y){
                 data.frame(
                   name = y[[which(names(y)=="name")]][[1]],
                   department = sapply(y[which(names(y)=="department")], function(x){x[[1]][[1]]}),
                   id = sapply(y[which(names(y)=="department")], function(x){attr(x, "id")})
                 )
               }))

    name department   id
1   Mary       Math  300
2   Mary    English  301
3   Mary    Chinese 302f
4   Mary      Music  317
5  Kevin    Physics 12G0
6  Kevin     German  321
7  Kevin     French  325
8  Kevin    Spanish  427
9   Andy    Swedish  330
10  Andy     Danish  331
11  Andy    Russian  332
12  Andy   Japanese  341
13  Nana     Arabic  200
14  Nana    African  201
15  Nana      Sport  202
16  Nana     Korean  211
17 Sandy     Vocals  100
18 Sandy   Language  515
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