[From nobody Thu Feb  8 13:50:40 2007
Message-ID: <45CB15DB.6000003@ema.fr>
Date: Thu, 08 Feb 2007 13:21:47 +0100
From: Olivier ETERRADOSSI <olivier.eterradossi@ema.fr>
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To: r-help@stat.math.ethz.ch
Subject: Re : Re: [R] setting a number of values to NA over  a data.frame.
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Hi John,

Unless I miss a point, why dont you try something like :

# some fake data
 > fake<-as.data.frame(cbind(seq(1,10,by=1),c(rep(1,4),rep(0,4),rep(2,2))))
      V1 V2
 1    1    1
 2    2    1
 3    3    1
 4    4    1
 5    5    0
 6    6    0
 7    7    0
 8    8    0
 9    9    2
10   10    2

# change 0 by NA
 > fake[fake==0]<-NA  # or fake$V2[fake$V2==0]<-NA if you don't want all 
0 in the dataframe to be changed to NA
# test
 > is.na(fake$V2)
[1] FALSE FALSE FALSE FALSE  TRUE  TRUE  TRUE  TRUE FALSE FALSE

Sorry if I did not understand the issue. Hope this helps. Olivier


Jim Lemon wrote :

> John Kane wrote:
>   
>> > This is probably a simple problem but I don't see a
>> > solution.
>> > 
>> > I have a data.frame with a number of columns where I
>> > would like 0 <- NA
>> > 
>>     
> Hi John,
> You might have a look at "toNA" in the prettyR package. Wait for version 
> 1.0-4, just uploaded, as I have fixed a bug in that function.
>
> Jim

-- 
Olivier ETERRADOSSI
Maître-Assistant
CMGD / Equipe "Propriétés Psycho-Sensorielles des Matériaux"
Ecole des Mines d'Alès
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