Say I have a list consisting of a range of integers from 1-10 with repetition and I want to remove all the 0s from that list, is there an easy way to go about doing that?
Something like na.omit but for my choice of elements?
Asked
Active
Viewed 69 times
-2
-
1Reproducible example? – Sotos Jul 07 '16 at 11:44
-
`x[ x == 0 ] – zx8754 Jul 07 '16 at 11:44
-
@Laterow, I don't think it's a duplicate, since this question aims at subsetting a `list` – loki Jul 07 '16 at 11:53
-
@zx8754 what is this process called (x[ x == 0 ] – Qwertford Jul 07 '16 at 12:07
-
1@Qwertford This is a combination of subsetting (`[`) and assignment (` – lmo Jul 07 '16 at 12:14
-
1Please read the info about [how to ask a good question](http://stackoverflow.com/help/how-to-ask) and how to give a [reproducible example](http://stackoverflow.com/questions/5963269). This will make it much easier for others to help you. – zx8754 Jul 07 '16 at 12:15
2 Answers
1
since you did not provide an example I create a list ls
ls <- list(rep(0:10, 10))
lsnew <- ls[[1]][ls[[1]] != 0]
It should be mentioned that lsnew is a numeric vector, not a list!
This is a simple example of subsetting in R. For further information on subsetting different data structures refer to:
loki
- 8,836
- 6
- 49
- 76
-
which package is this a part of? I looked in help and couldn't find it. – Qwertford Jul 07 '16 at 12:04
-
This is base R. You don't need any packages for lists. Some details on subsetting [here](http://adv-r.had.co.nz/Subsetting.html) – loki Jul 07 '16 at 12:07
-
Where can I learn to use those square brackets? Ive never seen them before and dont understand. what you've written. – Qwertford Jul 07 '16 at 12:13
-
http://www.cookbook-r.com/Basics/Getting_a_subset_of_a_data_structure/ or http://www.cookbook-r.com/Basics/Indexing_into_a_data_structure/ – loki Jul 07 '16 at 12:16
1
extending @loki's answer you can also exclude more than one element
ls <- list(rep(0:10, 10))
#excluding 0
lsnew <- ls[[1]][which(ls[[1]] != 0)]
#excluding 0 & 1
lsnew <- ls[[1]][! ls[[1]] %in% c(0,1)]
Latrunculia
- 686
- 1
- 6
- 15
-
I ment generalising to the exclusion of more than one element. I edited my answer to reflect that `which` is not needed. – Latrunculia Jul 07 '16 at 12:21