如何使用2個類別變量和1個數字變量的信息創建新變量

Question

我有一個數據集，看起來像這樣：

ID  Meal    Food    Amount
1   Lunch   Meat    50
1   Lunch   Potato  10
1   Dinner  Fish    105
1   Dinner  Rice    100
1   Dinner  Pulses  50
2   BF     Cereal   100
2   BF      Milk    200
2   Lunch   Rice    200
2   Lunch   Chicken 150
2   Lunch   Veg     100
2   Dinner  Pasta   200
2   Dinner  Meat    200
2   Dinner  Tomato  50
2   Dinner  Cheese  10

我想使用變量Food，Meal和Amount中的信息來創建幾個新變量，因此一行上只有一個ID。 因此，我將使用諸如Cereal_BF，Cereal_Lunch，Cereal_Dinner，Meat_BF，Meat_Lunch，Meat_Dinner，Potato_BF，Potato_Lunch，Potato_Dinner等變量，這些變量顯示來自變量Amount的對應信息。

謝謝您的幫助！

帕特里夏

Answer 1

您可以合並列，並使用tidyverse函數傳播它們。

dd %>% 
   unite(MealFood, Meal, Food) %>% 
   spread(MealFood, Amount)

哪里

dd<-read.table(text="ID  Meal    Food    Amount
1   Lunch   Meat    50
               1   Lunch   Potato  10
               1   Dinner  Fish    105
               1   Dinner  Rice    100
               1   Dinner  Pulses  50
               2   BF     Cereal   100
               2   BF      Milk    200
               2   Lunch   Rice    200
               2   Lunch   Chicken 150
               2   Lunch   Veg     100
               2   Dinner  Pasta   200
               2   Dinner  Meat    200
               2   Dinner  Tomato  50
               2   Dinner  Cheese  10", header=T, stringsAsFactors=F)