[R] Adding elements in an array where I have missing data.

[Berton Gunter]

Below.

> -----Original Message-----
> From: Gabor Grothendieck [mailto:ggrothendieck at gmail.com] 
> Sent: Tuesday, May 02, 2006 10:42 AM
> To: Berton Gunter
> Cc: John Kane; R R-help
> Subject: Re: [R] Adding elements in an array where I have 
> missing data.
> 
> On 5/2/06, Berton Gunter <gunter.berton at gene.com> wrote:
> > >
> > > Here are a few alternatives:
> > >
> > > replace(a, is.na(a), 0) + b
> > >
> > > ifelse(is.na(a), 0, a) + b
> > >
> > > mapply(sum, a, b, MoreArgs = list(na.rm = TRUE))
> > >
> >
> > Well, Gabor, if you want to get fancy...
> >
> > evalq({a[is.na(a)]<-0;a})+b
> >
> 
> Note that the evalq can be omitted:
> 
>    { a[is.na] <- 0; a } + b
> 

No it can't. The idea is **not** to change the original a.

-- Bert