[R] Column sums from a data frame (without the column headers)

jim holtman jholtman at gmail.com
Fri Feb 29 23:21:54 CET 2008


PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html and provide commented,
minimal, self-contained, reproducible code.

Here is an example; I am not sure what problem you are having with
'indexing' since you did not show an example.

> x <- data.frame(a=1:10, b=21:30, c=41:50)
> y <- colSums(x)
> y
  a   b   c
 55 255 455
> # indexing into y
> y[1]
 a
55
> # same as
> y["a"]
 a
55
>
>

On Fri, Feb 29, 2008 at 2:21 PM, Jason Horn <jhorn at bu.edu> wrote:
> Does anyone know how to get a vector of column sum from a data frame?
> You can use colSums(), but this gives you a object of type "numeric"
> with the column labels in the first row, and the sums in the second
> row.  I just want a vector of the sums, and I can't figure out a way
> to index the "numeric" object.
>
> Thanks!
>
> ______________________________________________
> R-help at 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 you are trying to solve?  Tell me what you want to
do, not how you want to do it.



More information about the R-help mailing list