用lhs的长度表示R中的子集a-规则

arules 包装 R 提取一些关联规则,并按左手边的长度(lhs)进行过滤。

我尝试使用子集,但没有成功。

  trans<-read.transactions(file='file.csv', format="single", sep=",",cols=c("userid","target"))

  inspect(head(trans,3))

  rules<-apriori(trans,parameter=list(support=0.06, confidence=0.5,minlen=3,maxlen=6)) 

  # sort by support
  top.support <- sort(rules, decreasing = TRUE, na.last = NA, by = "support")

这就是我要做的:

subset(rules,subset=length(lhs)==5) # not working. it return set of 0 rules