how to extract information from apriori R (association rules)

Question

I am doing some association rules mining in R and want to extract my results so I can build reports my results look like this:

> inspect(rules[1:3])
  lhs          rhs                         support confidence lift
1 {apples} => {oranges}                    0.00029       0.24  4.4
2 {apples} => {pears}                      0.00022       0.18 45.6
3 {apples} => {pineapples} 0.00014         0.12  1.8

How do i extract the "rhs" here i.e. a vector of oranges, pears and pineapples

Further how do I extract information out of the summary i.e.

> summary(rules)

The data type is "s4" and have no problem extracting when the output is in the list etc.. how do you do the equivelant? set of 3 rules

rule length distribution (lhs + rhs):sizes
2 
3 

   Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
      2       2       2       2       2       2 

I want to extract the "3" from the "set of 3 rules"

I have gotten as far as using "@" What does the @ symbol mean in R?

But once i use that, how do i turn my results into a vector i.e.

inspect(rules@rhs)
1 {oranges}
2 {pears}
3 {pineapples}

becomes character vector of length 3

Answer 1

To answer your second question:length(rules)

Now about your first question:

library("arules")
data("Adult")
## Mine association rules.
rules <- apriori(Adult,parameter = list(supp = 0.5, conf = 0.9, target = "rules"))
summary(rules)

l = length(rules)

everything = labels(rules)
#print(everything)

cut = unlist(strsplit(everything,"=> "))[seq(2,2*l,by=2)]
print(cut)

Don't hesitate if you have a question, this might be a bit dense :-)