difftime between rows using dplyr

Question

I\'m trying to calculate the time difference between two timestamps in two adjacent rows using the dplyr package. Here\'s the code:

    tidy_ex <- function ()         


        

Answer 1

Thanks to Victorp for the suggestion. I changed the mutate line to:

mutate(diff = c(difftime(tail(timestamp, -1), head(timestamp, -1)),0))

(The 0 I placed at the end so the difference calculation would start in the first row).