StructureClasses {methods} | R Documentation |
The virtual class structure
and classes that
extend it are formal classes analogous to S language structures such
as arrays and time-series.
## The following class names can appear in method signatures, ## as the class in as() and is() expressions, and, except for ## the classes commented as VIRTUAL, in calls to new() "matrix" "array" "ts" "structure" ## VIRTUAL
Objects can be created by calls of the form new(Class, ...)
,
where Class
is the quoted name of the specific class (e.g.,
"matrix"
), and the other arguments, if any, are interpreted as
arguments to the corresponding function, e.g., to function
matrix()
. There is no particular advantage over calling those
functions directly, unless you are writing software designed to work
for multiple classes, perhaps with the class name and the arguments
passed in.
The specific classes all extend class "structure"
, directly, and
class "vector"
, by class "structure"
.
as(x, "matrix")
calls as.matrix(x)
.S4groupGeneric
)
are defined for combinations of structures and vectors (including
special cases for array and matrix), implementing the concept of
vector structures as in the reference.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
showClass("structure") ## explore a bit : showClass("ts") (ts0 <- new("ts")) str(ts0) showMethods("Ops") # six methods from these classes, but maybe many more