[R] mirror vector?
Robin Hankin
r.hankin at noc.soton.ac.uk
Fri Jul 28 10:00:09 CEST 2006
Hi Antje
use the fact that n:1 counts backwards from n, and then use this as
a row index:
> m <- matrix(1:30,5,6)
> m[nrow(m):1,]
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 5 10 15 20 25 30
[2,] 4 9 14 19 24 29
[3,] 3 8 13 18 23 28
[4,] 2 7 12 17 22 27
[5,] 1 6 11 16 21 26
[
a more general answer would be
library(magic)
arev(m,1)
]
HTH
rksh
On 28 Jul 2006, at 08:50, <niederlein-rstat at yahoo.de> wrote:
> Hello,
>
> I'm an absolut beginner with R and now I got a 2D vector with
> numbers. I would like to mirror this vector now by the rows (so
> that the first row becomes last, second becomes one before last, ...).
> I don't know if there is any method I can use to do this.
> Could you please help me?
>
> Antje
>
>
> ---------------------------------
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--
Robin Hankin
Uncertainty Analyst
National Oceanography Centre, Southampton
European Way, Southampton SO14 3ZH, UK
tel 023-8059-7743
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