itemFrequencyPlot {arules} | R Documentation |
Provides the generic function itemFrequencyPlot
and the S4 method
to create an item frequency bar plot for inspecting
the item frequency distribution for objects based on
itemMatrix
(e.g.,
transactions
,
or items in
itemsets
and
rules
).
itemFrequencyPlot(x, ...) ## S4 method for signature 'itemMatrix': itemFrequencyPlot(x, type = "relative", cex.names = par("cex.axis"), ...)
x |
the object to be plotted. |
... |
further arguments are passed on (see
barplot from possible arguments). |
type |
indicates whether item frequencies should be displayed relative of absolute. |
cex.names |
expansion factor for axis names (bar labels). |
A numeric vector with the midpoints of the drawn bars; useful for adding to the graph.
Michael Hahsler
data(Adult_transactions) # the following example compares the item frequencies # of people with a rage income (boxes) with the average in the data set # box plot for young people (first 72 items) midpoints <- itemFrequencyPlot( Adult_transactions[Adult_transactions %in% "income = large", 1:72]) # add the item frequency over all transactions (first 72 items) lines(midpoints, itemSupport(Adult_transactions[, 1:72]))