喜歡的東西expand.grid名單

Question

我有存儲爲所謂的「DLIST」列出的清單三個文本文檔的列表上：

dlist <- structure(list(name = c("a", "b", "c"), text = list(c("the", "quick", "brown"), c("fox", "jumps", "over", "the"), c("lazy", "dog"))), .Names = c("name", "text")) 

在我腦子裏，我發現它有助於圖片DLIST是這樣的：

name text 
1 a  c("the", "quick", "brown") 
2 b  c("fox", "jumps", "over", "the") 
3 c  c("lazy", "dog") 

這怎麼能被操縱如下？這個想法是繪製它，所以可以熔化ggplot2的東西會很好。

name text 
1 a the 
2 a quick 
3 a brown 
4 b fox 
5 b jumps 
6 b over 
7 b the 
8 c lazy 
9 c dog 

這是每個單詞一行，同時提供單詞和其父文檔。

我曾嘗試：

> expand.grid(dlist) 
    name     text 
1 a  the, quick, brown 
2 b  the, quick, brown 
3 c  the, quick, brown 
4 a fox, jumps, over, the 
5 b fox, jumps, over, the 
6 c fox, jumps, over, the 
7 a    lazy, dog 
8 b    lazy, dog 
9 c    lazy, dog 

> sapply(seq(1,3), function(x) (expand.grid(dlist$name[[x]], dlist$text[[x]]))) 
    [,1]  [,2]  [,3]  
Var1 factor,3 factor,4 factor,2 
Var2 factor,3 factor,4 factor,2 

unlist(dlist) 
    name1 name2 name3 text1 text2 text3 text4 
    "a"  "b"  "c" "the" "quick" "brown" "fox" 
    text5 text6 text7 text8 text9 
"jumps" "over" "the" "lazy" "dog" 

> sapply(seq(1,3), function(x) (cbind(dlist$name[[x]], dlist$text[[x]]))) 
[[1]] 
    [,1] [,2] 
[1,] "a" "the" 
[2,] "a" "quick" 
[3,] "a" "brown" 

[[2]] 
    [,1] [,2] 
[1,] "b" "fox" 
[2,] "b" "jumps" 
[3,] "b" "over" 
[4,] "b" "the" 

[[3]] 
    [,1] [,2] 
[1,] "c" "lazy" 
[2,] "c" "dog" 

公平地說，我通過各種迷惑申請和plyr功能，真的不知道從哪裏開始。我從來沒有見過類似於上面的「僥倖」嘗試的結果，並且不理解它。

Answer 1

如果您將dlist轉換爲命名列表（我認爲更適合的結構），則可以使用stack()來獲取所需的兩列數據。

（該rev()和setNames()在第二行調用只是衆多方法來調整列的順序和名稱以匹配你的問題出所需的輸出之一。）

x <- setNames(dlist$text, dlist$name) 
setNames(rev(stack(x)), c("name", "text")) 
# name text 
# 1 a the 
# 2 a quick 
# 3 a brown 
# 4 b fox 
# 5 b jumps 
# 6 b over 
# 7 b the 
# 8 c lazy 
# 9 c dog 

Answer 2

Josh的答案是更甜但我想我會把我的帽子扔在戒指裏。

dlist <- structure(list(name = c("a", "b", "c"), 
    text = list(c("the", "quick", "brown"), 
    c("fox", "jumps", "over", "the"), c("lazy", "dog"))), 
    .Names = c("name", "text")) 

lens <- sapply(unlist(dlist[-1], recursive = FALSE), length) 

data.frame(name = rep(dlist[[1]], lens), text = unlist(dlist[-1]), row.names = NULL) 

## name text 
## 1 a the 
## 2 a quick 
## 3 a brown 
## 4 b fox 
## 5 b jumps 
## 6 b over 
## 7 b the 
## 8 c lazy 
## 9 c dog 

這就是說，列表清單是一種尷尬的存儲方法。向量列表（特別是向量列表）將更容易處理。

Answer 3

另一種解決方案，也許更普及：

do.call(rbind, do.call(mapply, c(dlist, FUN = data.frame, SIMPLIFY = FALSE))) 

#  name text 
# a.1 a the 
# a.2 a quick 
# a.3 a brown 
# b.1 b fox 
# b.2 b jumps 
# b.3 b over 
# b.4 b the 
# c.1 c lazy 
# c.2 c dog