[R] Basic question on applying a function to each row of a dataframe

[Ko-Kang Kevin Wang]

Hi,

You need to tell the apply() whether you want to apply the function to 
rows (1) or columns (2).

So in your case you may want to try something like:
  apply(DF, 1, foo)

On Sun, 8 Jun 2003, peter leonard wrote:

> I have a function foo(x,y) and a dataframe, DF,  comprised of two vectors, x 
> & w,  as follows :
> 
>    x w
> 1  1 1
> 2  2 1
> 3  3 1
> 4  4 1
> 
> etc
> 
> 
> I would like to apply the function foo to each 'pair' within DF e.g  
> foo(1,1), foo(2,1), foo(3,1) etc
> 
> I have tried
> 
> >apply(DF,foo)
> >apply(DF[,],foo)
> >apply(DF[DF$x,DF$w],foo)
> 

-- 
Cheers,

Kevin

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--
Ko-Kang Kevin Wang
Master of Science (MSc) Student
SLC Tutor and Lab Demonstrator
Department of Statistics
University of Auckland
New Zealand
Homepage: http://www.stat.auckland.ac.nz/~kwan022
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