Re: [R] mirror vector?

From: Uwe Ligges <ligges_at_statistik.uni-dortmund.de>
Date: Fri 28 Jul 2006 - 18:25:16 EST

Jacques VESLOT wrote:
> > mat <- matrix(1:16,4,4)
> > mat
> [,1] [,2] [,3] [,4]
> [1,] 1 5 9 13
> [2,] 2 6 10 14
> [3,] 3 7 11 15
> [4,] 4 8 12 16
> > apply(mat,2,rev)
> [,1] [,2] [,3] [,4]
> [1,] 4 8 12 16
> [2,] 3 7 11 15
> [3,] 2 6 10 14
> [4,] 1 5 9 13

or a lot faster:

mat[nrow(mat):1, ]

Uwe Ligges

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> niederlein-rstat@yahoo.de a écrit :

>> 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
>>
>>  		
>> ---------------------------------
>> Was Sie schon immer wissen wollten aber nie zu Fragen trauten? Yahoo! Clever hilft Ihnen.
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>>

>
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R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. Received on Fri Jul 28 18:30:25 2006

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