Sorting dataframe

Question

I have two dataframes of same dimensions. But as shown I want to order the dataframe datasuch that the id_num is ordered in the order of id_num of reference. The output should look like the dataframe required.

How can I do it?

reference <- data.frame(id_num=c(206,307,408,506), Event_1=0, Event_2=0)

data <- data.frame(id_num=c(506,307,408,206), Event_1=c(1,3,5,7), Event_2=c(2,4,6,8))

required <- data.frame(id_num=c(206,307,408,506), Event_1=c(7,3,5,1), Event_2=c(8,4,6,2))

Here is one option with `data.table` `nm1 <- names(reference)[-1];setDT(reference)[data, (nm1) := mget(paste0("i.", nm1)), on = .(id_num)]` — akrun, Jul 22 '17 at 13:01

score 2 · Accepted Answer · answered Jul 22 '17 at 13:03

2

merged <- merge(reference[,"id_num",drop=FALSE],data,by="id_num")

answered Jul 22 '17 at 13:03

mindlessgreen

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or just `merge(reference["id_num"], data)` – rawr Jul 22 '17 at 13:05

Sorting dataframe

1 Answers1