[R] date from weeknumber

[David Winsemius]

On Jul 20, 2010, at 6:37 PM, H Rao wrote:

> Hi,
>
> Is there a function to get the last(or first) day of the week, given  
> the
> week number of the year?
>
> For eg, week number for 7/20 is 29 as obtained by  
> format(Sys.Date(),"%U"),
> is there a function which returns 7/25 - the last day of week # 29
>

require(tis)
nthMon <- function(x) as.Date(currentMonday(xTi=as.Date("2010-01-01")) 
+7*(x-1))

 > nthMon(2)
[1] "2010-01-11"

Or:
  nthMonYr <- function(n, Yr)  
as.Date(currentMonday(xTi=as.Date(paste(Yr,"-01-01",sep="")))+7*(n-1))

 > nthMonYr(2,2010)
[1] "2010-01-11"

> TIA,
> Rao.
>
> 	[[alternative HTML version deleted]]
>
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