Question

I see that when Hadley Wickam prints data frame here, the values which dont change row over row dont get printed.

that is, instead of having :

name user rating
robuchon nicolas 2
robuchon nicolas 1
robuchon antoine 3
robuchon tartenpion 2
gagnaire nicolas 2
gagnaire christophe 2

it prints as such :

name user rating
robuchon nicolas 2
……………………….1
……………antoine 3
……………tartenpion 2
gagnaire nicolas 2
…………..christophe 2

where the dots are for spaces…

Does anyone knows how to do that ?

Answer 1

It’s from the use of cast(). The variables to the left of ~ are treated that way.

It must be a version of cast() that he is using because when he prints out non-cast data.frames, that behavior does not appear. Sorry, this answer doesn’t completely answer your question.

Another reason I think it is another version of cast() is that instead of showing (all), it shows .. This feature also appears in a paper by the author in 2005.