Question

I am just beginning to learn R and am having an issue that is leaving me fairly confused. My goal is to create an empty vector and append elements to it. Seems easy enough, but solutions that I have seen on stackoverflow don’t seem to be working.

To wit,

>     a <- numeric()
>     append(a,1)
[1] 1
>     a
numeric(0)

I can’t quite figure out what I’m doing wrong. Anyone want to help a newbie?

Answer 1

append does something that is somewhat different from what you are thinking. See ?append.

In particular, note that append does not modify its argument. It returns the result.

You want the function c:

> a <- numeric()
> a <- c(a, 1)
> a
[1] 1