# [R] Extracting subset of a vector

Peter Dalgaard p.dalgaard at biostat.ku.dk
Sat Oct 11 22:03:07 CEST 2008

```Megh Dal wrote:
> Thanks for this suggestion. However I am not getting :
>
> length(x) = length(x1) + length(x[ ! x %in% x1])
>
> Any better idea?
>
If you don't like the answer, you need to rephrase the question....
(what "remains" when you remove a value that occurs multiple times in x?)

x[-match(x1,x)] does not work either.

I think this does:
y <- x
for (z in x1) y <- y[-match(z,y)]

but is is much easier to do

ix <- sample(seq(along=x), 5)
x1 <- x[ix]
x2 <- x[-ix]

>
> --- On Sun, 10/12/08, Jorge Ivan Velez <jorgeivanvelez at gmail.com> wrote:
>
>
>> From: Jorge Ivan Velez <jorgeivanvelez at gmail.com>
>> Subject: Re: [R] Extracting subset of a vector
>> To: megh700004 at yahoo.com
>> Cc: r-help at stat.math.ethz.ch
>> Date: Sunday, October 12, 2008, 1:06 AM
>> Hi Megh,
>> Try this:
>>
>> x<-c(100,96,88,100,100,96,80,68,92,96,88,92,68,84,84,88,72,88,72,88)
>> x1 = sample(x, 5, replace=FALSE)
>>
>> x[ ! x %in% x1]
>>
>> HTH,
>>
>> Jorge
>>
>>
>> On Sat, Oct 11, 2008 at 3:25 PM, Megh Dal
>> <megh700004 at yahoo.com> wrote:
>>
>>
>>> I have 2 vecros :
>>>
>>>
>> x<-c(100,96,88,100,100,96,80,68,92,96,88,92,68,84,84,88,72,88,72,88)
>>
>>> x1 = sample(x, 5, replace=FALSE)
>>>
>>> Now i want to get remaining values of vector
>>>
>> "x" those are not member of
>>
>>> vector "x1". Can anyone please tell me how
>>>
>> to do that?
>>
>>> ______________________________________________
>>> R-help at r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>> PLEASE do read the posting guide
>>> http://www.R-project.org/posting-guide.html
>>> and provide commented, minimal, self-contained,
>>>
>> reproducible code.
>>
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

--
O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
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~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)              FAX: (+45) 35327907

```