How to insert one element into a vector?
Barry Rowlingson <B.Rowlingson at lancaster.ac.uk> writes:
michael watson (IAH-C) wrote:
There must be a million ways of doing this!
Actually I'd say there were no ways of doing this, since I dont
think you can actually insert into a vector - you have to create a new
vector that produces the illusion of insertion!
Here's a Q+D function that fails if you try and insert at the start,
or at the end. Its very D.
insert <- function(v,e,pos){
return(c(v[1:(pos-1)],e,v[(pos):length(v)]))
}
This is actually an exercise in a certain introductory book on R, with the intention of having the student do the obvious c(v[1:4],5,v[5:5]) style computation and maybe think a little about the edge effects. I only recently saw the somewhat unfortunately named append() function, which has been in S/R ever since the blue book...:
append(v,5,4)
[1] 1 2 3 4 5 6
O__ ---- Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk) FAX: (+45) 35327907