Hi
On 14 Jun 2005 at 3:24, Dave Evens wrote:
>
> Is it possible to make comparisons between numeric NAs
> and other numeric values?
everything is possible but I think you will need a special function.
e.g.
mytest<-function(x,y) {
d<-length(x)
testvec1<-is.na(x)+is.na(y)
firstno<-which(x[testvec1==0]==y[testvec1==0])
secondno<-which(testvec1==2)
thirdno<-which(testvec1==1)
result<-rep(F,d)
result[firstno]<-T
result[secondno]<-NA
result[thirdno]<-F
result
}
Which works with integers , but could give some wrong results
with floating point numbers.
HTH
Petr
>
> For example, if I have two vectors
>
> > x<-c(1:10,1:10,rep(NA,20))
> > y<-c(1:30,rep(NA,10))
>
> I want to compare them
>
> > x==y
> [1] TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE
> TRUE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
> FALSE FALSE FALSE NA NA NA NA NA
> [26] NA NA NA NA NA NA NA NA
> NA NA NA NA NA NA NA
>
> What I would like is to have TRUE for the first 10,
> FALSE for the next 20, and NA for the last 10. Is this
> possible?
>
> Thanks in advance for any help.
>
> Dave
>
>
>
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Petr Pikal
petr.pikal@precheza.cz
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