R help - Jan 2003 - replace NA´s

hey
what should I do to replace in a data frame NA?s with zeroes?
Thanks in advance
Juan Pablo

On Mon, Jan 13, 2003 at 05:15:02PM +0000, juan pablo perez
wrote:
> what should I do to replace in a data frame NA?s with zeroes?
I use lapply
> dd <- data.frame(a=c(1,2,NA,4),b=c(NA,2,3,4))
> dd
   a  b
1  1 NA
2  2  2
3 NA  3
4  4  4
> dd2 <- data.frame(lapply(dd,function(x,...){x[is.na(x)] <- 3.14159 ;
x}))
> dd2
        a       b
1 1.00000 3.14159
2 2.00000 2.00000
3 3.14159 3.00000
4 4.00000 4.00000

That will generate a warning message for each non-numeric column in
your data frame.  A tidier way is left as an exercise. ;)

Cheers

Jason
-- 
Indigo Industrial Controls Ltd.
64-21-343-545
jasont at indigoindustrial.co.nz

Dear Jason and Juan,

At 09:11 AM 1/14/2003 +1300, Jason Turner wrote:
>On Mon, Jan 13, 2003 at 05:15:02PM +0000, juan pablo perez wrote:
> > what should I do to replace in a data frame NA?s with zeroes?
>
>I use lapply
>
> > dd <- data.frame(a=c(1,2,NA,4),b=c(NA,2,3,4))
> > dd
>    a  b
>1  1 NA
>2  2  2
>3 NA  3
>4  4  4
> > dd2 <- data.frame(lapply(dd,function(x,...){x[is.na(x)] <-
3.14159 ; x}))
> > dd2
>         a       b
>1 1.00000 3.14159
>2 2.00000 2.00000
>3 3.14159 3.00000
>4 4.00000 4.00000
>
>That will generate a warning message for each non-numeric column in
>your data frame.  A tidier way is left as an exercise. ;)
Here's a pretty simple expression using a for loop over columns (and 
testing for numeric data):

         for(i in 1:ncol(dd)) if(is.numeric(dd[,i])) dd[is.na(dd[,i]), i] <-
0

I hope that this helps,
  John
____________________________
John Fox
Department of Sociology
McMaster University
email: jfox at mcmaster.ca
web: http://www.socsci.mcmaster.ca/jfox