percentage count by group using dplyr

Question

with a data frame df like below

df <- data.frame(colors = c(\"red\", \"blue\", \"green\", \"red\", \"red\" , \"blue\"))

I c

Answer 1

You can either pipe this to a mutate( prop = count / sum(count) ) or directly within summarise with nrow(.). Something like this:

df %>%
  group_by(colors) %>%
  summarise(count = n() / nrow(.) )

or

df %>%
  group_by(colors) %>%
  summarise(count = n() ) %>%
  mutate( prop = count / sum(count) )