[R] creating a reverse geometric sequence
    Erik Iverson 
    eriki at ccbr.umn.edu
       
    Sun May 23 19:43:16 CEST 2010
    
    
  
Hello,
Can anyone think of a non-iterative way to generate a decreasing geometric 
sequence in R?
For example, for a hypothetical function dg, I would like:
 > dg(20)
[1] 20 10 5 2 1
where I am using integer division by 2 to get each subsequent value in the 
sequence.
There is of course:
dg <- function(x) {
   res <- integer()
   while(x >= 1) {
     res <- c(res, x)
     x <- x %/% 2
   }
   res
}
 > dg(20)
[1] 20 10  5  2  1
This implementation of 'dg' uses an interative 'while' loop.  I'm simply 
wondering if there is a way to vectorize this process?
Thanks,
Erik
    
    
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