r - Split a string vector at whitespace

Question

I have the following vector:

tmp3 <- c("1500 2", "1500 1", "1510 2", "1510 1", "1520 2", "1520 1", "1530 2", 
"1530 1", "1540 2", "1540 1")

I would like to just retain the second number in each of the atoms of this vector, so it would read:

c(2,1,2,1,2,1,2,1,2,1)

Answer 1

There's probably a better way, but here are two approaches with strsplit():

as.numeric(data.frame(strsplit(tmp3, " "))[2,])
as.numeric(lapply(strsplit(tmp3," "), function(x) x[2]))

The as.numeric() may not be necessary if you can use characters...