[R] Insert elements into a vector in a defined positions

[Rolf Turner]

On 26/11/2009, at 10:46 AM, Manuel Ramon wrote:

>
> Dear R users,
> I have a vector of length n and I want to insert some elements (in  
> my case
> the NA string) into a defined positions. For example, my vector is  
> z1 and I
> want to add NA's in positions 4, 6 y 7 so after that, my new  
> vector, z2,
> should have a length of 10+3.
>
>   z1 <- 1:10
>   id <- c(4,6,7)
>
>   # And z2 should be:
>   z2 <- c(1,2,3,NA,4,5,NA,NA,6,7,8,9,10)
>
> Anyone knows how can I do that?

At first I thought append() might work ... but the "after"
argument to append seems to have to be of length 1.

How about:

	z2 <- numeric(length(z1)+length(id))
	z2[id] <- NA
	z2[!is.na(z2)] <- z1

A bit kludgy, but it appears to work.

	cheers,

		Rolf Turner

######################################################################
Attention:\ This e-mail message is privileged and confid...{{dropped:9}}