# [R] replacement has length zero

Peter Ehlers ehlers at ucalgary.ca
Sat Jul 7 21:44:24 CEST 2012

```On 2012-07-07 03:19, fabiano wrote:
> I have been working on the following code but keep getting an err message. My
> current thinking is that the problem is on the indexing but do not know how
> to fix it. Any help please?
>
> ungulate <-
> as.matrix(ungulate);colnames(ungulate)<-NULL;rownames(ungulate)<-NULL
> habitat <- habitat[,3]
> site <- site.data\$SiteId
> visit <- site.data\$Visit
> date <- site.data\$Date
> date <- matrix(date,nrow=20,ncol=7,byrow=TRUE)
> S <- dim(ungulate)[1]
> m <- 14	# number of augmented species
> G <- G[,2]
> g <- rep(NA,length=m)
> G <- c(G,g) # combined list with actual and augmented data set so in this
> case 6 + 14
> g <- length(table(G))
> # habitat id
> Hab <- cbind(seq(1,20),habitat) #habitat types for 20 sties run from 2 to 4
>
> hab <- matrix(NA,nrow=2,ncol=7)    #creating placing values to be filled
> with values generated by the following loop
> for(i in 1:4){
> 	hab[i,] <- Hab[habitat==i,1]   }   # want to use this loop to substitute NA
> by exact values as those found in the real data set which can be 2 to 4 but
> keep getting an error message saying
>
> Error in hab[i, ] <- Hab[habitat == i, 1] : replacement has length zero

Have you taken a look at just what 'Hab' and 'habitat' contain?
It looks to me that 'habitat' is not a set of integers which it
would have to be to get habitat==i to be TRUE. I guess that
Hab[habitat==i, 1] is the empty set (hence 'length zero').

Peter Ehlers

>
> Any help. Thanks
> Error in hab[i, ] <- Hab[habitat == i, 1] : replacement has length zero
>
> --
> View this message in context: http://r.789695.n4.nabble.com/replacement-has-length-zero-tp4635700.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help