shingles {lattice}  R Documentation 
Functions to handle shingles
shingle(x, intervals=sort(unique(x))) equal.count(x, ...) as.shingle(x) is.shingle(x) ## S3 method for class 'shingle': plot(x, panel, xlab, ylab, ...) ## S3 method for class 'shingle': print(x, showValues = TRUE, ...) ## S3 method for class 'shingleLevel': as.character(x, ...) ## S3 method for class 'shingleLevel': print(x, ...) ## S3 method for class 'shingle': summary(object, showValues = FALSE, ...) ## S3 method for class 'shingle': x[subset, drop = FALSE] as.factorOrShingle(x, subset, drop)
x 
numeric variable or R object, shingle in plot.shingle and
x[] . An object (list of intervals) of class "shingleLevel" in
print.shingleLevel

object 
shingle object to be summarized 
showValues 
logical, whether to print the numeric part. If FALSE, only the intervals are printed 
intervals 
numeric vector or matrix with 2 columns 
subset 
logical vector 
drop 
whether redundant shingle levels are to be dropped 
panel, xlab, ylab 
standard Trellis arguments (see
xyplot ) 
... 
other arguments, passed down as appropriate. For
example, extra arguments to equal.count are passed on to
co.intervals . graphical parameters can be passed as
arguments to the plot method.

A shingle is a data structure used in Trellis, and is a generalization
of factors to ‘continuous’ variables. It consists of a numeric
vector along with some possibly overlapping intervals. These intervals
are the ‘levels’ of the shingle. The levels
and
nlevels
functions, usually applicable to factors, also work on
shingles. The implementation of shingles is slightly different from
S.
There are print methods for shingles, as well as for printing the
result of levels()
applied to a shingle. For use in labelling,
the as.character
method can be used to convert levels of a
shingle to character strings.
equal.count
converts x
to a shingle using the equal
count algorithm. This is essentially a wrapper around
co.intervals
. All arguments are passed to co.intervals
.
shingle
creates a shingle using the given intervals
. If
intervals
is a vector, these are used to form 0 length
intervals.
as.shingle
returns shingle(x)
if x
is not a
shingle.
is.shingle
tests whether x
is a shingle.
plot.shingle
displays the ranges of shingles via
rectangles. print.shingle
and summary.shingle
describe
the shingle object.
x$intervals
for levels.shingle(x)
,
logical for is.shingle
, an object of class "trellis"
for
plot
(printed by default by print.trellis
), and
an object of class "shingle"
for the others.
Deepayan Sarkar Deepayan.Sarkar@Rproject.org
z < equal.count(rnorm(50)) plot(z) print(z) print(levels(z))