[R] subsetting tables

[Jannis]

Sorry If I miss the point you want to achieve, but why not just:


which(red > 0.5)

or 

red[which(red > 0.5)] 

if you want to use this col/row wise you could do:

apply(red, 1, function(x)x[x>0.5])
and
apply(red, 1, function(x)x[x>0.5])

?

--- netzwerkerin <lehmannk at informatik.uni-tuebingen.de> schrieb am Di, 6.9.2011:

> Von: netzwerkerin <lehmannk at informatik.uni-tuebingen.de>
> Betreff: [R] subsetting tables
> An: r-help at r-project.org
> Datum: Dienstag, 6. September, 2011 14:10 Uhr
> Hi guys,
> 
> one of the questions where you need a real human instead of
> a search engine,
> so it would be great if you could help. 
> 
> I have a matrix of z-scores which I would like to filter,
> sometimes
> columnwise, sometimes rowwise. Data looks like this:
> 
>   Allstar hsa.let.7a hsa.let.7a.1 hsa.let.7a.2
> 2    0.87   
>    0.79       
> -0.57         1.07
> 3    0.67      -1.14   
>     -0.78        -0.95
> 4   -0.46      -0.30 
>       -0.36     
>    1.14
> 
> Now I want to find all elements which are below/above some
> threshold. Subset
> works fine with the columns:
> 
> > subset(red[,4], red[,4] > 0.5)
> [1] 1.07 1.14
> 
> But not with the rows:
> 
> > subset(red[2,], red[2,] > 0.5)
>   Allstar hsa.let.7a hsa.let.7a.1 hsa.let.7a.2
> 3    0.67      -1.14   
>     -0.78        -0.95
> 
> If I try to find all values above 0.5 (any row, any column,
> I just need the
> number of entries), this is what I try (and get):
> 
> > subset(red[,], red[,] > 0.5)
>      Allstar hsa.let.7a hsa.let.7a.1
> hsa.let.7a.2
> 2       0.87   
>    0.79       
> -0.57         1.07
> 3       0.67     
> -1.14        -0.78     
>   -0.95
> NA        NA     
>    NA       
>    NA       
>    NA
> NA.1      NA     
>    NA       
>    NA       
>    NA
> NA.2      NA     
>    NA       
>    NA       
>    NA
> 
> Obviously I'm doing something wrong, but what?
> Help very much appreciated.
> Netzwerkerin
> 
> --
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> 
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