dplyr: “Error in n(): function should not be called directly”
问题 I am attempting to reproduce one of the examples in the dplyr package but this error message. I am expecting to see a new column n produced with the frequency of each combination. Can someone tell me what I am missing? I triple checked that the package is loaded. Thanks for the help, as always. library(dplyr) # summarise peels off a single layer of grouping by_vs_am <- group_by(mtcars, vs, am) by_vs <- summarise(by_vs_am, n = n()) Error in n() : This function should not be called directly 回答1