Stack/Melt 列集

Question

我正在尝试将单个 table 包含 10 列并将 merge/union/stack 分为 2 列。现在的布局是这样的

ID_1 | Name_1 | ID_2 | Name_2 | ID_3 | Name_3

我正在尝试将其转换为 headers "ID" 和 "Name"

列的格式

ID   | Name  
ID_1 | Name_1  
ID_2 | Name_2  
ID_3 | Name_3

Answer 1

示例数据

df <- data.frame( ID_1 = 1:10, Name_1 = LETTERS[1:10], 
ID_2 = 11:20, Name_2 = LETTERS[11:20])

   ID_1 Name_1 ID_2 Name_2
1     1      A   11      K
2     2      B   12      L
3     3      C   13      M
4     4      D   14      N
5     5      E   15      O
6     6      F   16      P
7     7      G   17      Q
8     8      H   18      R
9     9      I   19      S
10   10      J   20      T

代码

library( data.table )
#groups of how many columns?
numcols = 2
#set df as a data.table
data.table::setDT(df)
#split every two columns of df into list
L <- split.default( df, rep ( 1: (ncol(df)/numcols), each = numcols) )
#rowbind together
data.table::rbindlist(L, use.names = FALSE )

   ID_1 Name_1
1:    1      A
2:    2      B
3:    3      C
4:    4      D
5:    5      E
6:    6      F
7:    7      G
8:    8      H
9:    9      I
10:   10      J
11:   11      K
12:   12      L
13:   13      M
14:   14      N
15:   15      O
16:   16      P
17:   17      Q
18:   18      R
19:   19      S
20:   20      T

Answer 2

一个tidyverse解决方案。重塑您的数据两次以使其变长（先按名称重塑，然后按 ID 重塑）。使用 separate 查找名称和 ID 的“后缀”，然后过滤匹配的后缀。

library(tidyverse)
df %>%
    pivot_longer(cols = starts_with("Name"), names_to = "name_names", values_to = "name") %>%
    pivot_longer(cols = starts_with("ID"), names_to = "id_names", values_to = "id") %>%
    separate(col = name_names, into = c("name_names", "suffix_names")) %>%
    separate(col = id_names, into = c("id_names", "suffix_id")) %>%
    filter(suffix_names == suffix_id) %>%
    select(name, id)

# A tibble: 20 x 2
   name     id
   <fct> <int>
 1 A         1
 2 K        11
 3 B         2
 4 L        12
 5 C         3
 6 M        13
 7 D         4
 8 N        14
 9 E         5
10 O        15
11 F         6
12 P        16
13 G         7
14 Q        17
15 H         8
16 R        18
17 I         9
18 S        19
19 J        10
20 T        20

Stack/Melt 列集

Stack/Melt Sets of Columns

r

reshape

melt

tidyverse

data-wrangling