Question

我试图将列表转换为单个字符值，或者基本上是这样：

test <- data.frame(a = c(1,1,1,2,2,2), b = c("a", "b", "c", "d", "e", "f" )) %>% 
  group_by(a) %>% summarise(b = list(b))

到此：

test <- data.frame(a = c(1,2), b = c("a, b, c", "d, e, f" ))

Answer 1

你走了：

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Answer 2

根据OP的建议，我发表评论作为未来参考的答案。

从原始数据框开始，您可以执行以下操作：

data.frame(a = c(1,1,1,2,2,2), b = c("a", "b", "c", "d", "e", "f")) %>% 
   group_by(a) %>%
   summarise(b = paste(b, collapse = ","))

## A tibble: 2 x 2
#      a b    
#  <dbl> <chr>
#1  1.00 a,b,c
#2  2.00 d,e,f

r-list list列到字符向量，其中列表是字符

2 个答案: