structure returns the given object with further
an object which will have various attributes attached to it.
attributes, specified in
tag = value
form, which will be attached to data.
Adding a class
"factor" will ensure that numeric codes are
given integer storage mode.
For historical reasons (these names are used when deparsing),
".Label" are renamed to
It is possible to give the same tag more than once, in which case the
last value assigned wins. As with other ways of assigning attributes,
tag = NULL removes attribute
it is present.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.