我想添加一个新列SubCategory，其中的值根据Category列的值随机填充。详细信息如下：
Sub_Hair = c("Shampoo", "Conditioner", "Gel", "HairOil", "Dye")
Sub_Beauty = c("Face", "Eye", "Lips")
Sub_Nail= c("NailPolish", "NailPolishRemover", "NailArtKit", "ManiPadiKit")
Sub_Others = c("Electric", "NonElectric")
> product_data_1[1:10, c("Pcode", "Category", "MRP")]
Pcode Category MRP
1 16156L Beauty $8.88
2 16162M Others $21.27
3 16168M Others $2.98
4 16169E Nail $26.64
5 16207A Hair $6.38
6 17012B Beauty $33.03
7 17012C Beauty $20.58
8 17012F Beauty $36.29
9 17091A Nail $20.55
10 17107D Nail $28.20
我正在尝试下面的代码。但是，行正在更新，每个类别只有一个子类别。例如，所有具有"Beauty"类别的行，子类别为"Eye"，而不是从"Face，Eye and Lips"中随机选择的值。这是代码和输出：
product_data_1 = within(product_data_1, SubCategory[Category == "Beauty"] <- sample(Sub_Beauty, 1))
product_data_1 = within(product_data_1, SubCategory[Category == "Hair"] <- sample(Sub_Hair, 1))
product_data_1 = within(product_data_1, SubCategory[Category == "Nail"] <- sample(Sub_Nail, 1))
product_data_1 = within(product_data_1, SubCategory[Category == "Others"] <- sample(Sub_Others, 1))
> product_data_1[1:10, c("Pcode", "Category", "MRP", "SubCategory")]
Pcode Category MRP SubCategory
1 16156L Beauty $8.88 Eye
2 16162M Others $21.27 Electric
3 16168M Others $2.98 Electric
4 16169E Nail $26.64 NailPolish
5 16207A Hair $6.38 Gel
6 17012B Beauty $33.03 Eye
7 17012C Beauty $20.58 Eye
8 17012F Beauty $36.29 Eye
9 17091A Nail $20.55 NailPolish
10 17107D Nail $28.20 NailPolish
将子类别值放入类似subcat_list <- list(Hair = Hair, Beauty = Beauty, Nail = Nail, Others = Others)的列表中。然后，您可以使用product_data_1$Category对subcat_list进行切片，使用sapply对生成的向量列表的每个元素调用sample：
set.seed(323)
product_data_1$SubCategory <- sapply(subcat_list[product_data_1$Category], sample, 1)
您也可以使用dplyr+purrr:尝试稍微不同的方法
library(tidyverse)
product_data_1 %>%
mutate(SubCategory = map_chr(Category, ~ sample(subcat_list[[.]], 1)))
输出示例：
Pcode Category MRP SubCategory
1 16156L Beauty $8.88 Eye
2 16162M Others $21.27 Electric
3 16168M Others $2.98 Electric
4 16169E Nail $26.64 NailPolish
5 16207A Hair $6.38 Gel
6 17012B Beauty $33.03 Eye
7 17012C Beauty $20.58 Lips
8 17012F Beauty $36.29 Face
9 17091A Nail $20.55 ManiPadiKit
10 17107D Nail $28.20 NailArtKit
这里是一个基本的R解决方案。它使用了Hadley Wickham在这篇JSS文章中解释的拆分/应用/合并策略。
我将把Sub_*矢量放在一个列表Sub_list中。请注意，split将按Category对结果进行排序，因此列表Sub_list也必须按顺序排列向量。
Sub_list <- list(Sub_Beauty, Sub_Hair, Sub_Nail, Sub_Others)
sp <- split(product_data_1, product_data_1$Category)
set.seed(1234)
sp <- lapply(seq_along(sp), function(i){
sp[[i]]$SubCategory <- sample(Sub_list[[i]], nrow(sp[[i]]), replace = TRUE)
sp[[i]]
})
result <- do.call(rbind, sp)
result <- result[order(as.integer(row.names(result))), ]
result
# Pcode Category MRP SubCategory
#1 16156L Beauty $8.88 Eye
#2 16162M Others $21.27 NonElectric
#3 16168M Others $2.98 NonElectric
#4 16169E Nail $26.64 NailPolish
#5 16207A Hair $6.38 Shampoo
#6 17012B Beauty $33.03 Eye
#7 17012C Beauty $20.58 Face
#8 17012F Beauty $36.29 Lips
#9 17091A Nail $20.55 NailPolishRemover
#10 17107D Nail $28.20 ManiPadiKit
最终清理。
rm(Sub_list)
数据
product_data_1 <- read.table(text = "
Pcode Category MRP
1 16156L Beauty $8.88
2 16162M Others $21.27
3 16168M Others $2.98
4 16169E Nail $26.64
5 16207A Hair $6.38
6 17012B Beauty $33.03
7 17012C Beauty $20.58
8 17012F Beauty $36.29
9 17091A Nail $20.55
10 17107D Nail $28.20
", header = TRUE)