将一列重塑为r中的多列

Question

我有一个数据框架，如:

Groups COL1
G1     1
G2     3
G3     5
G1     7
G2     9
G3     11

并且我想将列Groups作为多个唯一列，例如:

G1 G2 G3 
1    1  3  5
2    7  9  8

有人有什么主意吗?

这里是玩具数据，如果它可以帮助:

structure(list(Groups = c("G1", "G2", "G3", "G1", "G2", "G3"), 
Col1 = c(1L, 3L, 5L, 7L, 9L, 11L)), class = "data.frame", row.names = c(NA, 
-6L))

Answer 1

编辑完成后，dplyr和tidyr的解决方案如下:

library(tidyverse)
df %>% 
pivot_wider(names_from = Groups,
values_from = Col1,
values_fn = list) %>% 
unnest(cols = c(G1,G2,G3))

输出:

G1    G2    G3
<int> <int> <int>
1     1     3     5
2     7     9    11

数据使用:

df <- structure(list(Groups = c("G1", "G2", "G3", "G1", "G2", "G3"), 
Col1 = c(1L, 3L, 5L, 7L, 9L, 11L)), class = "data.frame", row.names = c(NA, 
-6L))

Answer 2

另一个想法是:

df %>%
group_by(Groups) %>%
mutate(index = row_number()) %>%
pivot_wider(names_from = "Groups", values_from = "Col1")
# A tibble: 2 x 4
index    G1    G2    G3
<int> <int> <int> <int>
1     1     1     3     5
2     2     7     9    11

能在最后滴下index

Answer 3

我们可以从base R中使用unstack

unstack(df, Col1 ~ Groups)
G1 G2 G3
1  1  3  5
2  7  9 11