R help - Nov 2005 - Remove levels

Daer All,
 
I have a factor  variable, X with 5 levels. When I type tables(X) it gives me:
 
table(X)
1     2   3    4   5 
10   5    0   0   0
 
How to drop the levels with zeros such that when I will type:
table(X) it will give me:
 
table(X)
1     2   
10   5    
 
 
Thank a lot,
 
Bernard
 


		
---------------------------------


	[[alternative HTML version deleted]]

Marc Bernard wrote:
> Daer All,
>  
> I have a factor  variable, X with 5 levels. When I type tables(X) it gives
me:
>  
> table(X)
> 1     2   3    4   5 
> 10   5    0   0   0
>  
> How to drop the levels with zeros such that when I will type:
> table(X) it will give me:
>  
> table(X)
> 1     2   
> 10   5    

table(X[,drop=TRUE])

Uwe Ligges

>  
> Thank a lot,
>  
> Bernard
>  
> 
> 
> 		
> ---------------------------------
> 
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html

Marc Bernard <bernarduse1 at yahoo.fr> writes:
> Daer All,
>  
> I have a factor  variable, X with 5 levels. When I type tables(X) it gives
me:
>  
> table(X)
> 1     2   3    4   5 
> 10   5    0   0   0
>  
> How to drop the levels with zeros such that when I will type:
> table(X) it will give me:
>  
> table(X)
> 1     2   
> 10   5    
table(factor(X)) or table(X[drop=TRUE]) should do it. The latter runs
the former, but the intention might be clearer.

-- 
   O__  ---- Peter Dalgaard             ??ster Farimagsgade 5, Entr.B
  c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
 (*) \(*) -- University of Copenhagen   Denmark          Ph:  (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)                  FAX: (+45) 35327907

Hi

On 10 Nov 2005 at 14:32, Marc Bernard wrote:

Date sent:      	Thu, 10 Nov 2005 14:32:35 +0100 (CET)
From:           	Marc Bernard <bernarduse1 at yahoo.fr>
To:             	r-help at stat.math.ethz.ch
Subject:        	[R] Remove levels
> Daer All,
> 
> I have a factor  variable, X with 5 levels. When I type tables(X) it
> gives me:
> 
> table(X)
> 1     2   3    4   5 
> 10   5    0   0   0
> 
> How to drop the levels with zeros such that when I will type:
> table(X) it will give me:

see ?factor
table(factor(X))

HTH
Petr

> 
> table(X)
> 1     2   
> 10   5    
> 
> 
> Thank a lot,
> 
> Bernard
> 
> 
> 
> 
> ---------------------------------
> 
> 
>  [[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
> http://www.R-project.org/posting-guide.html
Petr Pikal
petr.pikal at precheza.cz