Message-ID: <Pine.LNX.4.44.0404161722360.18068-100000@gannet.stats>
Date: 2004-04-16T18:23:08Z
From: Brian Ripley
Subject: summary() with argument of class difftime (PR#6780)
In-Reply-To: <20040416162046.67F7F10495@slim.kubism.ku.dk>
Where does it say that summary() can be applies to difftime objects?
On Fri, 16 Apr 2004 hosking@watson.ibm.com wrote:
> Full_Name: J. R. M. Hosking
> Version: 1.9.0
> OS: Windows 2000
> Submission from: (NULL) (129.34.20.23)
>
>
> > dt<-as.Date("2002-03-04")-as.Date("2001-02-03")
> > jstr(dt)
> difftime(units:days)(1) 394
> > summary(dt)
> Error in Summary.difftime(..., na.rm = na.rm) :
> sum not defined for difftime objects
>
>
>
> When x is of class difftime, either sum(x) should be permitted or summary(x)
> should not try to compute the mean.
>
> (R 1.9.0, Windows binary from CRAN)
--
Brian D. Ripley, ripley@stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
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