Subsetting Itemsets, Rules and Transactions
Provides the generic function subset and S4 methods to subset
associations or transactions (itemMatrix) which meet certain conditions
(e.g., contains certain items or satisfies a minimum lift).
subset(x, ...) ## S4 method for signature 'itemMatrix' subset(x, subset, ...) ## S4 method for signature 'itemsets' subset(x, subset, ...) ## S4 method for signature 'rules' subset(x, subset, ...) ## S4 method for signature 'itemMatrix' subset(x, subset, ...)
x |
object to be subsetted. |
subset |
logical expression indicating elements to keep. |
... |
further arguments to be passed to or from other methods. |
subset works on the rows/itemsets/rules of x. The
expression given in subset will be evaluated using x,
so the items (lhs/rhs/items) and the columns in the quality
data.frame can be directly referred to by their names.
Important operators to select itemsets containing items specified by their
labels are
%in% (select itemsets matching any given item),
%ain% (select only itemsets matching all given item),
%oin% (select only itemsets matching only the given item),
and %pin% (%in% with partial matching).
An object of the same class as x containing only the
elements which satisfy the conditions.
Michael Hahsler
data("Adult")
rules <- apriori(Adult)
## select all rules with item "marital-status=Never-married" in
## the right-hand-side and lift > 2
rules.sub <- subset(rules, subset = rhs %in% "marital-status=Never-married"
& lift > 2)
## use partial matching for all items corresponding to the variable
## "marital-status"
rules.sub <- subset(rules, subset = rhs %pin% "marital-status=")
## select only rules with items "age=Young" and "workclass=Private" in
## the left-hand-side
rules.sub <- subset(rules, subset = lhs %ain%
c("age=Young", "workclass=Private"))Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.