[Rd] cut.POSIXt problem with breaks= "quarter" (PR#14162)

[shmunde at googlemail.com]

Full_Name: Qing Xia
Version: 2.10.0
OS: Windows XP
Submission from: (NULL) (213.71.23.233)


I find, when I use "cut" function to cut date-time objects based on breaks =
"quarter", there exists a problem. It means, if the date-time has "JJJJ-MM-30"
or "JJJJ-MM-31", then "cut" runs not correctly, it gives wrong levels. Detail
can be found in the following R-Output:

1. correct Output levels, if there is no date-time "JJJJ-MM-30" or "JJJJ-MM-31"

> x<- as.Date(c("2009-03-21","2009-03-24"))
> cut(x, breaks= "quarter")
[1] 2009-01-01 2009-01-01
Levels: 2009-01-01


2. wrong Output levels, if there exists date-time "JJJJ-MM-30" or "JJJJ-MM-31"

> x<- as.Date(c("2009-03-21","2009-03-30"))
> cut(x, breaks= "quarter")
[1] 2009-01-01 2009-01-01
Levels: 2009-01-01 2009-04-01


> x<- as.Date(c("2009-03-21","2009-03-31"))
> cut(x, breaks= "quarter")
[1] 2009-01-01 2009-01-01
Levels: 2009-01-01 2009-04-01