因素

Question

我具有各種dataframes像：

Var1 "Bananas" "Apples" "Oranges" 
Freq "2"  "2"  "1"    


Var2 "Bananas" "Carrots" "Strawberries" "Apples" 
Freq "3"  "2"  "3"   "4"    

和作爲輸出我想一個數據幀/表/相似給每個輸入數據幀的出現，包括0出現在東西很好的概述。所以像這樣：

Var  "Bananas" "Apples" "Oranges" "Carrots" "Strawberries" 
Sample1 "2"  "2"  "1"  "0"   "0" 
Sample2 "3"  "4"  "0"  "2"   "3" 

我不能完全弄清楚任何解決方案，尤其是因爲data.frames不允許不同的長度。

Answer 1

注意到，NA和0意味着完全不同的東西。看看幫助文件?dplyr::join

library(dplyr) 
df1 <- data.frame(Var1 =c("Bananas", "Apples", "Oranges"), 
      Freq =c(2,2,1)) 
df2 <- data.frame(Var1 =c("Bananas", "Carrots", 
          "Strawberries", "Apples"), 
        Freq =c(3,2,3,4)) 
full_join(df1,df2, by = "Var1") 

Answer 2

你應該?merge看一看：

set.seed(1234) 
dat1 <- data.frame(var1 = LETTERS[1:5], freq = sample(1:100, 5)) 
dat2 <- data.frame(var2 = LETTERS[3:7], freq = sample(1:100, 5)) 

res <- merge(dat1, dat2, by.x = "var1", by.y = "var2", all = TRUE) 
res[is.na(res)] <- 0 
res 
# var1 freq.x freq.y 
# 1 A  12  0 
# 2 B  62  0 
# 3 C  60  65 
# 4 D  61  1 
# 5 E  83  23 
# 6 F  0 100 
# 7 G  0  50