Muri Soares wrote:
>Hi everyone,
>
>I have a matrix that contains 1000 replicates of a sample of a list of values.
>I want to group each row (row=replicate) into my defined bin ranges and then
>calculate the mean and stdev for each of the bin ranges (so I will have 1000
>rows but ncol=number of bin ranges).
>I don't know how to group rows in a matrix matrix according to another vector
>(which is what I think I need to do).
>
>Thanks for the help,
>Muri
>
>
>
Hi,
you may try this, once your factor grouping the rows is defined (here
noted 'fac') :
> A=matrix(1:12,ncol=3)
> A
[,1] [,2] [,3]
[1,] 1 5 9
[2,] 2 6 10
[3,] 3 7 11
[4,] 4 8 12
> fac=factor(c(1,1,2,2))
> split(A,fac)
$`1`
[1] 1 2 5 6 9 10
$`2`
[1] 3 4 7 8 11 12
> groupeA = lapply(split(A,fac),matrix,ncol=ncol(A))
> groupeA
$`1`
[,1] [,2] [,3]
[1,] 1 5 9
[2,] 2 6 10
$`2`
[,1] [,2] [,3]
[1,] 3 7 11
[2,] 4 8 12
And then you can perform any action on these matrices using lapply or
sapply.
Regards,
Thibaut.
--
######################################
Thibaut JOMBART
CNRS UMR 5558 - Laboratoire de Biométrie et Biologie Evolutive
Universite Lyon 1
43 bd du 11 novembre 1918
69622 Villeurbanne Cedex
Tél. : 04.72.43.29.35
Fax : 04.72.43.13.88
[EMAIL PROTECTED]
http://lbbe.univ-lyon1.fr/-Jombart-Thibaut-.html?lang=en
http://pbil.univ-lyon1.fr/software/adegenet/
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