[R] Element by Element addition of the columns of a Matrix

Uwe Ligges ligges at statistik.tu-dortmund.de
Sun May 1 18:11:09 CEST 2011



On 29.04.2011 15:06, Pete Brecknock wrote:
> ... is the apply function what you are looking for?
>
> A=matrix(1,2,4)
>
> apply(A,1,sum)


Thanks for providing answers to R-help, but:

1. Please quote the original question for the mailing list readers of us.
2. Please reply also to the original poster who may not be subscribed to 
the list.
3. In order to do the above more efficient, you actually want to use
rowSums(A) rather than the apply() version given above.

Best,
Uwe Ligges





> HTH
>
> Pete
>
>
>
>
> --
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> Sent from the R help mailing list archive at Nabble.com.
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