On 15-Dec-09 13:35:36, Jorge Ivan Velez wrote:> Dear Maithili,
> Here are two suggestions:
>
># data set
> x <- read.table(textConnection("Name no_of_instances
> AAA 12
> AA 17
> A 0
> BBB 11
> BB 6
> B 0
> C 8
> D 3"), header = TRUE)
> closeAllConnections()
> x
>
># option 1
> do.call(c,with(x, tapply(no_of_instances, Name, runif)))
>
># option 2
> with(x, runif( sum(no_of_instances) ))
>
> HTH,
> Jorge
And, to round off the above:
names(x) <- rep(Name,times=no_of_instances)
(or similar). Then you can extract the random numbers for any Name.
Ted.
> On Tue, Dec 15, 2009 at 8:26 AM, Maithili Shiva <> wrote:
>
>> Dear R helpers
>>
>> I have following table
>>
>> Name no_of_instances
>> AAA 12
>> AA 17
>> A 0
>> BBB 11
>> BB 6
>> B 0
>> C 8
>> D 3
>>
>> Now I need to generate the uniform random numbers (against the no. of
>> instances) and assign these numbers generated against the respective
>> names.
>> E.g. I need to generate 12 random numbers and assign these numbers
>> against
>> AAA.
>>
>> Individually I can generate them as
>>
>> AAA_no = c(runif(12))
>> AA_no = c(runif(17))
>> ......
>>
>> and so on.
>>
>> And in the end I can club them as
>>
>> ran_nos = c(AAA_no, AA_no, ..........D_no)
>>
>> My problem is if there are say 1000 names, then it will be a
>> cumbersome
>> job to generate 1000 individual random number sets and then to combine
>> them
>> to form a single dataset.
>>
>> Is there any alternative to this?
>>
>> Thanking in advance
>>
>> With regards
>>
>> Maithili
>>
>>
>>
>>
>> The INTERNET now has a personality. YOURS! See your Yahoo!
>> Homepage.
>> [[alternative HTML version deleted]]
>>
>>
>> ______________________________________________
>> 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.
>>
>>
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> 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.
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Date: 15-Dec-09 Time: 13:57:50
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