top_n versus order in r

Question

I am having trouble understanding the output from dplyr\'s top_n function. Can anybody help?

n=10

df = data.frame(ref=sample(letters,n),score=rnorm(n))

req         


        

Answer 1

My misunderstanding and expectation was due to my reading of the documentation linked to in the question and described in the comments. Despite some documentation claims, top_n does not generated output ordered by wt.

Answer 2

Both outputs are the same, but top_n is not rearranging the rows.

You can get the same result as df[order(df$score,decreasing = T)[1:5],] using arrange()

top_n(df, 5, score) %>% arrange(desc(score))

Flipping the ordering around, df[order(df$score,decreasing = F)[1:5],] is equivalent to top_n(df, -5, score) %>% arrange(score).