?sample

efficient enough?> system.time(z <- sample(1:5, 500000, TRUE,
prob=c(.05,.05,.05,.05,.8)))
   user  system elapsed
   0.12    0.02    0.14
> table(z)
z
     1      2      3      4      5
 24800  24771  25039  25022 400368
>


On Sat, Sep 20, 2008 at 3:43 PM, John Sorkin <jsorkin@grecc.umaryland.edu>wrote:

> R 2.6
> Windows XP
>
> I need to select from the integers 1,2,3,4,5 with some pre-determined
> probability, e.g. probability of selecting 5 80%, probability of selecting 1
> or  2 or  3 or 4 20%. Any suggestions for how I might accomplish this? I
> need to do it very efficiently as I will be doing it 500,000 times.
> Thanks
> John
>
> John David Sorkin M.D., Ph.D.
> Chief, Biostatistics and Informatics
> University of Maryland School of Medicine Division of Gerontology
> Baltimore VA Medical Center
> 10 North Greene Street
> GRECC (BT/18/GR)
> Baltimore, MD 21201-1524
> (Phone) 410-605-7119
> (Fax) 410-605-7913 (Please call phone number above prior to faxing)
>
> Confidentiality Statement:
> This email message, including any attachments, is for ...{{dropped:22}}

