[R] Creating quarterly data

[Thomas Jensen]

Thanks, Allan, that did the trick :)

Best, Thomas
On Jun 28, 2010, at 6:13 PM, Allan Engelhardt wrote:

> One approach:
>
> d <- data.frame(x1=c(2,3,4,1,5,8), x2=c(4,1,6,4,6,5), time=1:6)
> d$quarter <- (d$time-1) %/% 4  #  Or whatever your logic is
> aggregate(cbind(x1,x2) ~ quarter, data = d, sum)
> #   quarter x1 x2
> # 1       0 10 15
> # 2       1 13 11
>
>
> Hope this helps
>
> Allan
>
>
> On 28/06/10 13:23, Thomas Jensen wrote:
>> Dear R Experts,
>>
>> I have data in the following format
>>
>> x1    x2    time
>> 2    4    1
>> 3    1    2
>> 4    6    3
>> 1    4    4
>> 5    6    5
>> 8    5    6
>> .    .    .
>> .    .    .
>> .    .    .
>> 1    5    399
>> 3    4    400
>>
>> Time represents each month which simply has a number from 1 to 400  
>> (i.e. the data covers 400 months). I would like to somehow create  
>> two new variables which counts x1 and x2 as quarterly data in stead  
>> of monthly. Like this:
>>
>> x1    x1    Quarter
>> 10    12    1
>> 12    15    2
>> .    .    .
>> .    .    .
>> .    .    .
>> 23    21    100
>>
>> Can any one tell me how this can be done in R?
>>
>> With kind regards,
>> Thomas Jensen
>>
>> ______________________________________________
>> 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.