[R] Help Needed on Merging Columns by Summation

[Dennis Murphy]

Hi:

Based on the information you provided, I would suggest looking into
the transform() and within() functions in base R, and perhaps the
mutate() function in package plyr.

HTH,
Dennis

On Tue, Jun 21, 2011 at 11:35 PM, Nabila Binte Zahur <nabila at nus.edu.sg> wrote:
> Dear Sirs/Madam,
>
> I am a beginner to R, and I am currently working on a data matrix which looks like this:
>
>> head(oligo)
>
>        ko:K00001 ko:K00003 ko:K00005 ko:K00008 ko:K00009 ko:K00010 ko:K00012
> AAA       370          631                  365               67           164             455       491
> KAA       603         1208                 170              157        68                495       922
> NAA        60         110                     10                7            44               51        94
> DAA       183         802                    41               62          26              166       263
> CAA        58            12                    58                1               1              23         8
> TAA       451          468                  201                90       131              320       518
>
>
> For certain specific columns, I need to merge the columns in such a way that the elements get added together.
>
> For example, in order to merge the first and the second columns, my output for the first row shld be
>
>           ko:K00001/ko:K00003
> AAA       1001 (i.e. 370+631)
> KAA        1811 (i.e. 603+1208)
>
>
> and so on for the whole column.
>
> A colleague suggested using rowsum, but that seems to add up all the rows for ALL the columns and not just specified ones. Also, the output doesnt contain the column or row headers.
>
> Could you please suggest a solution?
>
> Yours sincerely
> Nabila Binte Zahur
>
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