How to fill zero in vector at alternate position in R

Question

I am new to R language. I came to a situation where I need to fill the zero at alternate Position in the vector. for Example:

v<-c(1,2,3,4,5,6,7,8,9,10)

I need the new vector like

0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 0 10

I tried with for loop to fill the zero but I am not able to do.

Several answers [here](http://r.789695.n4.nabble.com/Interleaving-elements-of-two-vectors-td795123.html) — A5C1D2H2I1M1N2O1R2T1, Feb 11 '13 at 05:28

score 8 · Answer 1 · answered Feb 11 '13 at 05:25

8

I am sure there are plenty of solutions, but

as.vector(rbind(0,v))
 [1]  0  1  0  2  0  3  0  4  0  5  0  6  0  7  0  8  0  9  0 10

will do it.

answered Feb 11 '13 at 05:25

thelatemail

@thelatemail.. Thanks a lot its working fine. I like this approach very much it is very precise way though Tyler's answer is also precise both answer are good and useful for me :) – Saurabh Feb 11 '13 at 07:23

mnel · Accepted Answer · 2013-02-11T05:29:46.070

6

A couple of approaches

Create a vector of zeros and then replace the correct indices

x1 <- rep(0, length(x)*2)
x1[seq(2,20,by=2)] <- x

or use Map and c

 unlist(Map(c,0,x))

edited Feb 11 '13 at 05:29

answered Feb 11 '13 at 05:23

mnel

Dang less characters than my response +1 – Tyler Rinker Feb 11 '13 at 05:37
I don't think so. I get `18` for mine, `16` for yours – mnel Feb 11 '13 at 05:41
Yay back on top but now I've wasted extra key strokes with my comments :( – Tyler Rinker Feb 11 '13 at 05:43
@ thanks mnel really your answer is helpful for me :) – Saurabh Feb 11 '13 at 07:24

score 3 · Answer 3 · answered Feb 11 '13 at 05:29

3

Just for kicks:

v <- c(1,2,3,4,5,6,7,8,9,10)
c(mapply(c, 0, v))

answered Feb 11 '13 at 05:29

Tyler Rinker

3 Answers3