[R] ISOdate returns incorrect date?

[Peter Dalgaard]

"Heiko Schaefer" <heiko.schaefer at swissrisk.com> writes:

> Does this really work for you? I still get:
> > ISOdate(1900,6,16)
> [1] "1900-06-15 14:00:00 Westeuropäische Sommerzeit"
> > ISOdate(1900,6,16,tz="")
> [1] "1900-06-15 12:00:00 Westeuropäische Sommerzeit"
> 
> Obviously the time son influences the time, but it can
> Not possibly account for the difference of a full day?!
> 
> Still puzzled...

Yes, something is strange for me too (RedHat 8):

> ISOdate(1900,3,1)
[1] "1900-03-01 13:00:00 CET"
> ISOdate(1900,3,2)
[1] "1900-03-01 13:00:00 CET"

Apparently, the one-day shift affects all dates after March 2, 1900,
and in no other year. One easily gets the suspicion that the fact that
1900 was *not* a leap year has something to do with it. However,
strptime() which this calls indirectly is only as good as its OS-level
counterpart, I believe. 

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
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