R - 数据框操作答案

【问题标题】：R - Dataframe manipulationR - 数据框操作
【发布时间】：2021-06-28 08:50:13
【问题描述】：

我有如下表

Food	Fried	Boiled
Egg	3	2
Fish	5	3

这个Dataframe的代码是

Names = c("Food", "Fried", "Boiled")
Egg = c("Egg", 3, 2)
Fish = c("Fish", 5, 3)
df = as.data.frame(rbind(Egg, Fish)) 
colnames(df) = Names; rownames(df) = NULL

我想将 Dataframe 操作为以下

Food	Fried/Boiled
Egg	Fried
Egg	Fried
Egg	Fried
Egg	Boiled
Egg	Boiled
Fish	Fried
Fish	Fried
Fish	Fried
Fish	Fried
Fish	Fried
Fish	Boiled
Fish	Boiled
Fish	Boiled

第 2 列“Fried/Boiled”为第一个表中的 Fried 和 Boiled 的每个值分别显示一个新行。

提前致谢！

【问题讨论】：

标签： r dataframe group-by aggregate data-manipulation

【解决方案1】：

这行得通吗：

library(dplyr)
library(tidyr)
df %>% pivot_longer(cols = -Food) %>% type.convert(as.is = T) %>% uncount(value)
# A tibble: 13 x 2
   Food  name  
   <chr> <chr> 
 1 Egg   Fried 
 2 Egg   Fried 
 3 Egg   Fried 
 4 Egg   Boiled
 5 Egg   Boiled
 6 Fish  Fried 
 7 Fish  Fried 
 8 Fish  Fried 
 9 Fish  Fried 
10 Fish  Fried 
11 Fish  Boiled
12 Fish  Boiled
13 Fish  Boiled

【讨论】：