| order {base} | R Documentation |
Ordering Permutation
Description
order returns a permutation which rearranges its first
argument into ascending order, breaking ties by further arguments.
sort.list is the same, using only one argument but allowing
partial sorting.
Usage
order(...)
sort.list(x, partial)
Arguments
... |
a sequence of vectors, all of the same length. |
x |
a vector. |
partial |
vector of indices for partial sorting. |
Details
In the case of ties in the first vector, values in the second are used to break the ties. If the values are still tied, values in the later arguments are used to break the tie (see the first example).
NA values are treated as greater than any other values
so that permutations returned by order move NA
values to the top end of the array.
partial is supplied for compatibility with S, but the sorting
is always complete.
See Also
sort and rank.
Examples
(ii <- order(x <- c(1,1,3:1,1:4,3), y <- c(9,9:1), z <-c(2,1:9)))
## 6 5 2 1 7 4 10 8 3 9
rbind(x,y,z)[,ii] # shows the reordering (ties via 2nd & 3rd arg)
## rearrange matched vectors so that the first is in ascending order
x <- c(5:1, 6:8, 12:9)
y <- (x - 5)^2
o <- order(x)
rbind(x[o], y[o])