如何在R中连接值和公共列

我试图通过旋转数据帧将所有值与唯一列值连接起来

var = c("X","X","Y","Z","Z","Z")
value =c(1,4,7,21,3,45)
df = data.frame(var,value)

o/p

---

提前感谢

我们可以将

聚合

与

c

一起使用：

aggregate(value ~ var, data = df, c)

  var     value
1   X      1, 4
2   Y         7
3   Z 21, 3, 45

---

您可以拆分数据集，并对值系列执行任何操作：

var = c("X","X","Y","Z","Z","Z")
value =c(1,4,7,21,3,45)
df = data.frame(var,value)

dflist <- split(df, df$var)

sapply(dflist, function(x) paste(x$value, collapse = ","))

---

使用

dplyr

df %>%
  mutate(value = paste0("(",value,")")) %>%
  group_by(var) %>%
  summarise_at(vars(value), paste, collapse = ",")

    X         Y         Z 
"1,4"       "7" "21,3,45" 

df %>%
  mutate(value = paste0("(",value,")")) %>%
  group_by(var) %>%
  summarise_at(vars(value), paste, collapse = ",")