Variant of fct_relabel with group sizes

[jl5000]

Would it be useful to include a function which quickly modifies factor values with information about how many rows take that value? e.g.

fac <- factor(c("A","A","B","C","C","C"))
with levels A B C

fct_relabel_with_counts(fac)
with levels 'A (n=2)' 'B (n=1)' 'C (n=3)'

This would be useful for including on plots. I'm sure this would get used a lot.

[hadley]

This feels a little too specialised to me, but maybe fct_relabel() could also supply the length of the factor as an additional second argument. Then you could do:

x %>% fct_relabel(~ paste(.x, "(n=", .y, ")"))

[jl5000]

That's probably a better solution.

[hadley]

Related to #257