[R] Fwd: duplicates

[ONKELINX, Thierry]

Does this works? (Untested)

library(plyr)
ddply(your_dataframe, "var1", function(x){
	x[which.max(x$var2), ]
})


----------------------------------------------------------------------------
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek
team Biometrie & Kwaliteitszorg
Gaverstraat 4
9500 Geraardsbergen
Belgium

Research Institute for Nature and Forest
team Biometrics & Quality Assurance
Gaverstraat 4
9500 Geraardsbergen
Belgium

tel. + 32 54/436 185
Thierry.Onkelinx op inbo.be
www.inbo.be

To call in the statistician after the experiment is done may be no more than asking him to perform a post-mortem examination: he may be able to say what the experiment died of.
~ Sir Ronald Aylmer Fisher

The plural of anecdote is not data.
~ Roger Brinner

The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data.
~ John Tukey
  

> -----Oorspronkelijk bericht-----
> Van: r-help-bounces op r-project.org 
> [mailto:r-help-bounces op r-project.org] Namens Dévaványai Agamemnón 
> Verzonden: donderdag 29 juli 2010 16:31
> Aan: r-help op r-project.org
> Onderwerp: [R] Fwd: duplicates
> 
>  
> 
> -- Eredeti üzenet --
> Feladó: Dévaványai Agamemnón  
> <devavanyai op citromail.hu>Címzett: r-hel op r-project.org, 
> r-hel op r-project.orgElküldve: 2010. július 29. 16:29Tárgy : duplicates
> 
>  Sorry!
> I try it again
> 
> Dear R Users!
> 
> 
> I have a dataframe with duplicatecases. Var1 duplicated by var2. 
> 
> 
> 
>  var1 var2  var3  var4  var5
> 1        4       500     1    2
>  1        3       200     2    5
>  1        8       125     1    9
>  2        2       120     2    52
>  2        6        22      1    20
> 2        9        400    1    22
> 3        1        100    2    8
> 3        2        200    5    40
>  4        8        20      1    60
> 
> I want to delete duplicate ones from var1 which have low rank 
> at var2, and keep that case which has highest rank at var2. I 
> would like to keep the Whole row (with the other variables: 
> 
> var1     var2     var3    var4    var5    
> 1          8          125     1         9
> 2          9           400    1        22
> 3          2           200    50     40
> 4           8          200     1      60
> 
>  Thanks Ag
> 
> 	[[alternative HTML version deleted]]
> 
> 

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