[R] : how to select rows at random

jim holtman jholtman at gmail.com
Fri Mar 27 20:21:05 CET 2009


I meant type in "?sample" to see what the 'sample' function does.  For
example, to select 50 random rows,

> sample(2000,50)
 [1] 1004  857 1219 1850  480  543 1466 1498 1854  922 1713  621  414
1830  105  817  906  825 1329 1500 1806 1623  186  352 1270 1727 1170
518 1743  370  964   20  710  870  248 1227  594  471  704 1751
[41] 1942 1435 1944 1057  849 1886  290  130   48 1195
>


On Fri, Mar 27, 2009 at 3:18 PM, Laura Rodriguez Murillo
<laura.lmurillo at gmail.com> wrote:
> Sorry, I'm attaching part of the file I have. They go up to 2000 and I
> would like to take a subset of around 300.
>
>
> 5001 1
> 5001 2
> 5001 3
> 5001 5
> 5001 6
> 5002 1
> 5002 2
> 5002 5
> 5002 6
> 5002 11
> 5002 15
> 5002 16
> 5003 1
> 5003 2
> 5003 5
> 5003 6
> 5004 1
> 5004 2
> 5004 5
> 5004 6
> 5004 10
> 5004 11
> 5004 12
> 5004 15
> 5004 16
> 5004 25
> 5004 26
> 5004 35
> 5004 36
> 5004 45
> 5004 46
> 5004 55
>
>
> Thank you!
>
> Laura
>
> 2009/3/27 jim holtman <jholtman at gmail.com>:
>> ?sample
>>
>> On Fri, Mar 27, 2009 at 3:11 PM, Laura Rodriguez Murillo
>> <laura.lmurillo at gmail.com> wrote:
>>> Hi dear list,
>>>
>>> I have a list of around 2000 identifiers aranged in a dataframe in one
>>> column and I would like to choose a random subset of these. I wonder
>>> if somebody can tell me if I could do this with R...
>>>
>>> Thank you so much!
>>>
>>> Laura RM
>>>
>>> ______________________________________________
>>> 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.
>>>
>>
>>
>>
>> --
>> Jim Holtman
>> Cincinnati, OH
>> +1 513 646 9390
>>
>> What is the problem that you are trying to solve?
>>
>



-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?




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