summary() with argument of class difftime (PR#6780)
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) Oxford OX1 3TG, UK Fax: +44 1865 272595