R help - Oct 2010 - adding a named column to a Matrix

Hello all,

I am trying to use cbind to add a named empty column to a Matrix:

outputmatrix <- cbind(outputmatrix,kog_id = seq(0,0,0))

The problem I have is that kog_id is a variable that has a value e.g.
"KOG1234", but I when I try to use this to name the added column, it
is named literally "kog_id" instead of "KOG1234".

How can I name a column by passing in a variable for the column name?
I am performing this action inside of a for loop, so I can't
necessarily know the position of the column in order to name it after
it is created.

Thanks,

Alison Callahan
-----------------------
PhD Candidate
Department of Biology
Carleton University

Try this:

`colnames<-`(cbind(m, kog_id = 0), c(colnames(m), kog_id))


On Wed, Oct 13, 2010 at 5:44 PM, Alison Callahan
<alison.callahan@gmail.com>wrote:
> Hello all,
>
> I am trying to use cbind to add a named empty column to a Matrix:
>
> outputmatrix <- cbind(outputmatrix,kog_id = seq(0,0,0))
>
> The problem I have is that kog_id is a variable that has a value e.g.
> "KOG1234", but I when I try to use this to name the added column,
it
> is named literally "kog_id" instead of "KOG1234".
>
> How can I name a column by passing in a variable for the column name?
> I am performing this action inside of a for loop, so I can't
> necessarily know the position of the column in order to name it after
> it is created.
>
> Thanks,
>
> Alison Callahan
> -----------------------
> PhD Candidate
> Department of Biology
> Carleton University
>
> ______________________________________________
> 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.
>


-- 
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O

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On Oct 13, 2010, at 4:44 PM, Alison Callahan wrote:
> Hello all,
>
> I am trying to use cbind to add a named empty column to a Matrix:
>
> outputmatrix <- cbind(outputmatrix,kog_id = seq(0,0,0))
Not sure off the top of my head what the right way might be, but this  
should work:

names(outputmatrix)[ which( names(outputmatrix) == "kog_id")] <-
kog_id
>
> The problem I have is that kog_id is a variable that has a value e.g.
> "KOG1234", but I when I try to use this to name the added column,
it
> is named literally "kog_id" instead of "KOG1234".
>
> How can I name a column by passing in a variable for the column name?
> I am performing this action inside of a for loop, so I can't
> necessarily know the position of the column in order to name it after
> it is created.
>
> Thanks,
>
> Alison Callahan

David Winsemius, MD
West Hartford, CT