R: How can I reorder the rows of a matrix, data.frame or vector according to another one.
- by John
test1 <- as.matrix(c(1, 2, 3, 4, 5))
row.names(test1) <- c("a", "b", "c", "d", "e")
test2 <- as.matrix(c(6, 7, 8, 9, 10))
row.names(test2) <- c("e", "d", "c", "b", "a")
test1
[,1]
a 1
d 2
c 3
b 4
e 5
test2
[,1]
e 6
d 7
c 8
b 9
a 10
How can I reorder test2 so that the rows are in the same order as test1? e.g:
test2
[,1]
a 10
d 7
c 8
b 9
e 6
I tried to use the reorder function with: reorder (test1, test2) but I could not figure out the correct syntax. I see that reorder takes a vector, and I'm here using a matrix. My real data has one character vector and another as a data.frame. I figured that the data structure would not matter too much for this example above, I just need help with the syntax and can adapt it to my real problem.