想請問data.frame新增欄位失敗的問題

[jhihchao]

#我用R內建的iris想新增一個column "Type"

iris$Type <- 0

#然後想根據iris$Sepal.Length是否超過5.5，設定iris$Type是 "長" 或 "短"

ifelse(iris$Sepal.Length > 5.5, iris$Type <- "長", iris$Type <- "短")

#console跑出的結果如下，可以正確顯示Type的長短

 [1] "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "長" "長" "短"
 [18] "短" "長" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短"
 [35] "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "短" "長"
 [52] "長" "長" "短" "長" "長" "長" "短" "長" "短" "短" "長" "長" "長" "長" "長" "長" "長"
 [69] "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "短" "短" "長" "長" "短"
 [86] "長" "長" "長" "長" "短" "短" "長" "長" "短" "長" "長" "長" "長" "短" "長" "長" "長"
[103] "長" "長" "長" "長" "短" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長"
[120] "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長"
[137] "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長" "長"

#但當我再回過頭看iris的data.frame時，發現Type那欄全部都是短。使用table()函數算長、短各有多少個

table(iris$Type)

#顯示出來的都是短

短
150 

想請問要怎麼修改這個問題？感謝各位先進。

[WEPA ^_^]

Hi friend,

修改為以下內容:

iris$Type <- ifelse(iris$Sepal.Length > 5.5, "長", "短")

# end

jhihchao 在 2022年11月17日 星期四凌晨1:17:15 [UTC+8] 的信中寫道：