Question

给定数据框和表中定义的一组规则。

df <- rbind(c("blue","M",9),c("blue","F",11))
colnames(df)<-c("eyes","gender","age")

rule <- rbind(c("blue","M","<10",1),c("blue","M",">10",2),c("blue","F","<10",3),c("blue","F",">10",4))
colnames(rule)<-c("eyes","gender","age","category" )

R中是否有办法在不重写if else脚本的情况下应用规则？

结果应如下所示：

 eyes   gender age  category
"blue"   "M"     9    1
"blue"   "F"     11   4

Answer 1

require(magrittr); require(dplyr)
# Convert to data.frame
rule %<>% data.frame(stringsAsFactors = F)
df %<>% data.frame(stringsAsFactors = F)

#left join on eyes and gender, then remove rows where age doesn't match

result <- df %>% 
            left_join(rule, by = c('eyes', 'gender'))%>% 
            filter(paste(age.x, age.y) %>% sapply(function(x) eval(parse(text = x)))) %>% 
            select(-age.y)

R中的决策表

1 个答案: