[R] how to create duplicated ID in multi-records per subject dataset

[markleeds at verizon.net]

  andrew has a point which makes my solution wrong. you'd have to change 
the factors to numerics and I'm not sure what
would happen when you did that. if you want to send a sample file of 
your data, that would be best but andrew's suggestion may
work right off the bat.



On Sun, Dec 14, 2008 at  9:19 PM, andrew wrote:

> if the records are in the file dupIDs.txt, then when you read them in,
> the IDs become factors.  Coercing them to numeric gets them to assign
> a unique number to each factor.
>
> So, you could try the following:
>
> dupIDs <- read.table("dupIDs.txt", header = T)
> dupIDs$ID2 <- cummax(as.numeric(dupIDs$ID)-1)
>
>> dupIDs
>   ID record ID2
> 1  1     20   1
> 2  .     30   1
> 3  .     25   1
> 4  2     26   2
> 5  .     15   2
> 6  3     21   3
>
> HTH,
>
> Andrew.
>
>
> On Dec 15, 12:56 pm, "Zhixin Liu" <z... at efs.mq.edu.au> wrote:
>> Hi R helpers,
>>
>> If I have a dataset looks like:
>> ID   record
>> 1        20
>> .         30
>> .         25
>> 2         26
>> .         15
>> 3         21
>> 4.....................
>>
>> And I want it becomes
>> ID   record
>> 1        20
>> 1        30
>> 1        25
>> 2         26
>> 2        15
>> 3         21
>> 4.....................
>>
>> That is, I have to duplicate IDs for those with multiple records. I 
>> am wondering it is possible to be done in R, and I am grateful if you 
>> would like to show me the direction.
>>
>> Many thanks!
>>
>> Zhixin
>>
>> ______________________________________________
>> R-h... at r-project.org mailing 
>> listhttps://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting 
>> guidehttp://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.