column of dates into time series
On Nov 29, 2009, at 7:52 AM, Linlin Yan wrote:
There is no year() function. Maybe you can try format() instead. On Sun, Nov 29, 2009 at 8:44 PM, DispersionMap <frenchcr at btinternet.com
wrote: i have a column of dates in this format: data[,"Raised.Date"] <- as.Date(data[,"Raised.Date"], "%d/%m/%Y"); data[1:10,"Raised.Date"] [1] "2006-07-07" "2006-07-07" "2006-04-03" "2006-04-03" "2006-04-03" "2006-04-03" "2006-04-03" "2006-04-03" "2006-04-03" "2006-04-03" I can turn them into months like this... Month<-months(data[,"Raised.Date"]) Month[1:10] [1] "July" "July" "April" "April" "April" "April" "April" "April" "April" "April" But i also want to turn them into years (and also weeks later on), so tried this...
library(chron)
?cut.dates
The argument breaks has several options including one of c("days",
"weeks", "months", "year")
> dts <- Sys.Date() - 1:20
> cut(dts, breaks="weeks")
[1] 2009-11-23 2009-11-23 2009-11-23 2009-11-23 2009-11-23
2009-11-23 2009-11-16 2009-11-16 2009-11-16 2009-11-16
[11] 2009-11-16 2009-11-16 2009-11-16 2009-11-09 2009-11-09 2009-11-09
2009-11-09 2009-11-09 2009-11-09 2009-11-09
Levels: 2009-11-09 2009-11-16 2009-11-23
I was a bit puzzled when I tried cut.dates as the function which
throws a function not found error.
Year<-year(data[,"Raised.Date"]) Error: could not find function "year"
David Winsemius, MD Heritage Laboratories West Hartford, CT