From edd at debian.org  Tue Jan 31 21:50:07 2012
From: edd at debian.org (Dirk Eddelbuettel)
Date: Tue, 31 Jan 2012 14:50:07 -0600
Subject: [Rd] seq.Date bug?
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On 31 January 2012 at 15:28, Sarah Goslee wrote:
| As Duncan pointed out, this is documented in ?seq.POSIXt:
| 
|      Using ?"month"? first advances the month without changing the day:
|      if this results in an invalid day of the month, it is counted
|      forward into the next month: see the examples.
| 
| But ?seq.Date gives the impression that the construct Dirk and I tried
| should work:
| 
|      ## find all 7th of the month between two dates, the last being a 7th.
|      st <- as.Date("1998-12-17")
|      en <- as.Date("2000-1-7")
|      ll <- seq(en, st, by="-1 month")
|      rev(ll[ll > st & ll < en])
| 
| is given as an example, and it is not pointed out that this won't work for
| the 30th of the month. Normally one can extrapolate from patterns given
| in the examples, and here that isn't true. So perhaps the help should
| be modified slightly instead?

Yup, that would indeed help with this "infelicity".

Dirk

-- 
"Outside of a dog, a book is a man's best friend. Inside of a dog, it is too
dark to read." -- Groucho Marx



[Rd] seq.Date bug?
Dirk Eddelbuettel