[R] Replacing 0s with NA

[Gavin Simpson]

On Fri, 2009-06-12 at 09:55 +0100, Christine Griffiths wrote:
> Hello
> 
> I have a dataset in which I would like to replace 0s with NAs. There is a 
> lot of information on how to replace NAs with 0, but I have struggled to 
> find anything with regards to doing the reverse. Any recommendations would 
> be great.

Here is one way:

## some dummy data
set.seed(123)
dat <- matrix(rnorm(100), ncol = 10)
## add some 0's
dat[sample(100, 20)] <- 0
## convert to df
dat <- data.frame(dat)
dat

## now replace 0 with NA
## replacement function
foo <- function(x) {
    x[x == 0] <- NA
    x
}
## lapply it, and force back to df
dat2 <- data.frame(lapply(dat, foo))
dat2

HTH

G

> 
> Cheers
> Christine
> 
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