function order
On 04/06/2011 08:35 PM, Yan Jiao wrote:
Dear All
I'm trying to sort a matrix using function order,
Some thing really odd:
e.g.
abc<-cbind(c(1,6,2),c(2,5,3),c(3,2,1))## matrix I want to sort
if I do
abc[ order(abc[,3]), increasing = TRUE]
the result is correct
[,1] [,2] [,3]
[1,] 2 3 1
[2,] 6 5 2
[3,] 1 2 3
But if I want to sort in decresing order:
abc[ order(abc[,3]), decreasing = TRUE]
the result is wrong
[,1] [,2] [,3]
[1,] 2 3 1
[2,] 6 5 2
[3,] 1 2 3
Also if I use
abc[ order(abc[,3]), increasing = FALSE]
it returns nothing
[1,]
[2,]
[3,]
Why is that?
Hi Yan, It is because you have put the "decreasing" argument outside the parentheses, and it is not being used in the "order" function. Jim