unsplit method for List object and split<-
method for Vector object.## S3 method for class 'List':
unsplit(value, f, drop = FALSE)
## S3 method for class 'Vector':
split(x, f, drop = FALSE, ...) <- valuefactor or list of factorsXFUNunsplit unlists value, where the order of the returned
vector is as if value were originally created by splitting that
vector on the factor f. split(x, f, drop = FALSE) <- value: Virtually splits x by
the factor f, replaces the elements of the resulting list with the
elements from the list value, and restores x to its original
form. Note that this works for any Vector, even though split
itself is not universally supported.