try this:
> myData
sample1.id1 sample1.id2 sample2.id1 sample1.id3 sample3.id1
sample1.id4 sample2.id2
1 1 2 2 1 1
1 1
2 1 2 2 2 1
2 1
3 1 2 2 3 1
3 1
4 1 2 2 4 1
4 1
5 1 2 2 5 1
5 1
6 1 2 2 6 1
6 1
7 1 2 2 7 1
7 1
8 1 2 2 8 1
8 1
9 1 2 2 9 1
9 1
10 1 2 2 10 1
10 1
> newData <- NULL
> for (i in repeat_ids){
+ # determine the columns to use
+ colIndx <- grep(paste(i, "$", sep=''), colnames(myData))
+ if (length(colIndx) == 0) next # make sure it exists
+ # create the average of the columns
+ newData <- cbind(newData, rowMeans(myData[, colIndx], na.rm=TRUE))
+ colnames(newData)[ncol(newData)] <- i # add the name
+ }
> newData
id1 id2
[1,] 1.333333 1.5
[2,] 1.333333 1.5
[3,] 1.333333 1.5
[4,] 1.333333 1.5
[5,] 1.333333 1.5
[6,] 1.333333 1.5
[7,] 1.333333 1.5
[8,] 1.333333 1.5
[9,] 1.333333 1.5
[10,] 1.333333 1.5
>
On Tue, Sep 7, 2010 at 12:00 PM, Juliet Hannah <juliet.han...@gmail.com> wrote:
> Hi Group,
>
> I have a data frame below. Within this data frame there are samples
> (columns) that are measured more than once. Samples are indicated by
> "idx". So "id1" is present in columns 1, 3, and 5. Not every id is
> repeated. I would like to create a new data frame so that the repeated
> ids are averaged. For example, in the new data frame, columns 1, 3,
> and 5 of the original will be replaced by 1 new column that is the
> mean of these three. Thanks for any suggestions.
>
> Juliet
>
>
>
> myData <- data.frame("sample1.id1" =rep(1,10),
> "sample1.id2"=rep(2,10),
> "sample2.id1" = rep(2,10),
> "sample1.id3" = 1:10,
> "sample3.id1" = rep(1,10),
> "sample1.id4" = 1:10,
> "sample2.id2" = rep(1,10))
>
> repeat_ids <- c("id1","id2")
>
> ______________________________________________
> R-help@r-project.org 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.
>
--
Jim Holtman
Cincinnati, OH
+1 513 646 9390
What is the problem that you are trying to solve?
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and provide commented, minimal, self-contained, reproducible code.
