[R] How to pool a group of samples and take the ave.

[affy snp]

Thanks Jim. It is way simple. Great.
Is there any function like rowMedians() which
could take the median value across samples?

Allen

On Nov 12, 2007 3:10 PM, jim holtman <jholtman at gmail.com> wrote:
> Try something like this:
>
> myAvg <- rowMeans(A[,48:243])
> B <- A[1:47,] / myAvg
>
>
> On Nov 12, 2007 1:37 PM, affy snp <affysnp at gmail.com> wrote:
> > Dear list,
> >
> > Hi! I have a table A, 238304 rows and 243 columns (representing
> > samples). First of all, I would like to pool a group of samples
> > from 48th column to 243rd column and take the average across
> > them and make a single column,saying as the reference column.
> >
> > Second, I want to use each column of first 47 columns in table
> > A divided by the reference column and end up with a new table
> > B with 238304 rows and 47 columns.
> >
> > Is there any simple code which especially could do sth like
> >       reference_column<-(A[,48]+A[,49]+...A[,243])/196
> > and B<-A[,1:47]/reference_column?
> >
> > Thank you very much for your help!
> >
> > Best,
> >      Allen
> >
> > ______________________________________________
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> > and provide commented, minimal, self-contained, reproducible code.
> >
>
>
>
> --
> Jim Holtman
> Cincinnati, OH
> +1 513 646 9390
>
> What is the problem you are trying to solve?
>