[R] Re : Re: setting a number of values to NA over a data.frame.

[John Kane]

--- Olivier ETERRADOSSI <olivier.eterradossi at ema.fr>
wrote:

> Hi again,
> 
> Awfully sorry John, I should have been sleeping and
> did not see your 
> full post....
> 
> here is a way, unless I miss the point again :
> 
>
fake<-as.data.frame(cbind(seq(1,10,by=1),c(rep(1,4),rep(0,4),rep(2,2))))
> 
> # from my previous post
> 
> # one moree column this time !
> fake3<-cbind(fake,fake$V2)
> index<-c(2,3)
> fake3[,index][fake3[,index]==0]<-NA
> 
> not nice, but seems to do the job.
> Hope this helps... this time :-)
> Olivier

That looks like it and is similar to one Haris
suggested. I think I was messing up the fake3[,index]
reference somehow.

 I need to make my explanations a bit clearer. 

Thanks



> 
> > Date: Thu, 08 Feb 2007 13:21:47 +0100
> From: Olivier ETERRADOSSI
> <olivier.eterradossi at ema.fr>
> To:  r-help at stat.math.ethz.ch
> Subject: Re : Re: [R] setting a number of values to
> NA over  a data.frame.
> 
> 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
> Hélioparc, 2 av. P. Angot, F-64053 PAU CEDEX 9
> tel std: +33 (0)5.59.30.54.25
> tel direct: +33 (0)5.59.30.90.35 
> fax: +33 (0)5.59.30.63.68
> http://www.ema.fr
> 
> 
>