如何将多个列表转换为一个数据帧

Question

我有一个列表，告诉你一个人有多少可能的伴侣。它看起来是这样的：

列表：

$`A1`
[1] "D2" "E2" "F2" "H2"
$`B1`
[1] "G2" "I2" "J2" "K2" "L2"
$`C1`
[1] "J2" "M2" "N2" "O2" "P2"
[6] "Q2" "R2" "S2"

例如，个体A1的可能伴侣是个体D2、个体E2、个体F2和个体H2。

我想把它变成一个数据框架，把一个个体和它可能的伴侣配对。所以我想要这样的东西：

df：

Female ID   Mate ID
       A1        D2    
       A1        E2
       A1        F2
       A1        H2
       B1        G2
       B1        I2
       B1        J2
       B1        K2
       B1        L2
       C1        J2
       C1        M2
       C1        N2
       C1        O2
       C1        P2
       C1        Q2
       C1        R2
       C1        S2

Answer 1

我喜欢purrr:map_df来解决这个问题：

您的数据

L <- list(A1 = c("D2", "E2", "F2", "H2"),
    B1 = c("G2", "I2", "J2", "K2", "L2"),
    C1 = c("J2", "M2", "N2", "O2", "P2", "Q2", "R2", "S2"))

解决方案

library(purrr)
map_df(L, ~data.frame("Mate.ID" = .x), .id="Female.ID")

   # Female.ID Mate.ID
# 1         A1      D2
# 2         A1      E2
# 3         A1      F2
# 4         A1      H2
# 5         B1      G2
# etc

我喜欢map_df，因为它有一个有用的.id参数，可以附加列表条目的名称。

(这也可以写成...)

map_df(L, function(i) data.frame("Mate.ID" = i), .id="Female.ID")

(...the .x是function(i) i的缩写)

Answer 2

一种仅使用base R的解决方案：

mylist <- list(A1=c("D2", "E2", "F2", "H2"),
            B1=c("G2", "I2", "J2", "K2", "L2"),
            C1=c("J2", "M2", "N2", "O2", "P2", "Q2", "R2", "S2"))

mydf <- lapply(1:length(mylist), function(i) {
    data.frame(`Female ID`=names(mylist)[i], `Mate ID`=mylist[[i]], stringsAsFactors=F, check.names=F)
})

mydf <- do.call(rbind, mydf)

Answer 3

你可以从R-开始使用stack -

L <- list(A1 = c("D2", "E2", "F2", "H2"),
    B1 = c("G2", "I2", "J2", "K2", "L2"),
    C1 = c("J2", "M2", "N2", "O2", "P2", "Q2", "R2", "S2"))

result <- stack(L)
names(result) <- c("MaleID", "FemaleID")

result

   MaleID FemaleID
1      D2       A1
2      E2       A1
3      F2       A1
4      H2       A1
5      G2       B1
6      I2       B1
7      J2       B1
8      K2       B1
9      L2       B1
10     J2       C1
11     M2       C1
12     N2       C1
13     O2       C1
14     P2       C1
15     Q2       C1
16     R2       C1
17     S2       C1