I'm just reading the book "R in a Nutshell". And it seems as if I skipped the part where the "." as in "sample.formula" was explained.
> sample.formula <- as.formula(y~x1+x2)
Is sample an object with a field formula as in other languages? And if so, how can I find out, what other fields/functions this object has? (Type declaration)
EDIT: I just found another confusing use of the ".":
> svm(formula = is_spam~., data = spambase.training)
(the dot between ~., )