[R] data.frame indexing

[Hans-Jörg Bibiko]

On 28.04.2008, at 16:40, Georg Ehret wrote:

> E.g.:
>> a<-as.data.frame(matrix(rnorm(100),nrow=10,ncol=10))
>> b<-which(a$V1>0.8)
>> b
> [1]  1  4  6 10
>> a_indexb<-a[b,]
>> a_notIndexB<-a[!b,]
>> nrow(a_notIndexB)
> [1] 0
>
> Indexing a on b is not a problem (a_indexb), but how can do get  
> only the
> elements left if I take out the elements indexed with b?

The ! operator only works on BOOLEAN.

ONE possible way to set a_notIndexB is:

a_notIndexB <-a [-1*b, ]

--Hans