Counting number of levels within another variable level in data frame

Question

I have a data frame with two character variables, state and birds. I'm trying to see how many bird types are within each state. I have tried:

data.frame %>%
   group_by(state) %>%
   n_distinct(data.frame$bird)

data.frame %>%
   group_by(state) %>%
   n_distinct(unique(data.frame$bird))

However, I am very stuck. Thank you in advance for your help; let me know if I need to add more clarification.

Answer 1

How about this?

data.frame %>%
   group_by(state) %>%
   summarize(distinct_birds = n_distinct(data.frame$bird))

Answer 2

This will be very simple using data.table

library(data.table)
dt=data.table(data.frame)

dt[,counts:=.N, by=.(state,birds)]

• .N is the data.table function to get counts
• by include grouping variables.

Answer 3

Also using tidyverse:

library(tidyverse)

data.frame %>% count(state)