How can I extarct rules which in lhsonly one special Item appear
1 {231050} => {231051} 0.06063479 1.0000000 16.492183
2 {231050,231051} => {275001} 0.05490568 0.9055145 6.576661
3 {231050,275001} => {231051} 0.05490568 1.0000000 16.492183
I would like to extract only first row in which I have only one 231050
arules has a subset function (see ?arules::subset), which you can use to draw a subset of rules meeting your criteria - like specific items on lhs, minimum support etc:
library(arules)
data("Adult")
rules <- apriori(Adult, parameter = list(supp = 0.5, conf = 0.9, minlen = 2))
item <- "race=White"
rules.sub <- subset(rules, lhs %in% item & size(lhs)==1)
inspect(rules.sub)
# lhs rhs support confidence lift
# 7 {race=White} => {native-country=United-States} 0.7881127 0.9217231 1.0270761
# 8 {race=White} => {capital-gain=None} 0.7817862 0.9143240 0.9966616
# 9 {race=White} => {capital-loss=None} 0.8136849 0.9516307 0.9982720