Just a small detail and I don't know whether it is of relevance or not. Following the "Hands-on programming with R" book in the chapter about Classes I entered the following code (## indicates console output):
die = 1:6
dim(die) <- c(2, 3)
According to the book the class of die in the end should be "matrix" only. For some reason my R turned the first row into a matrix and the second row into an array. Does anyone know the reason for that and how this can be resolved?