[R] selecting from a series of integers with pre-determined probabilities

[John Sorkin]

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)

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