My question is about how to select and rearrange the data to a new data frame Here is an example: Samples counts time A 10 3 A 12 4 A 11 3 B 12 4 B 10 5 C 11 2 C 13 3 Say, if I want to make a new table that only look at “counts” as below: A B C 10 12 11 12 10 13 11 How can I do this in R? Thank you! .