One other point that supports your hypothesis is that Excel 2000 on Windows 2000 has a problem in 1900 too. Enter a date into a cell and then enter =60 and it gives the date as Feb 29, 1900 even though 1900 is not a leap year.
Windows Excel uses 1900 as the origin for time but when Microsoft later created the Mac version of Excel they changed the origin to 1904 -- presumably they had realized their error by that time. Excel 2000 allows you to change the default origin from 1900 to 1904 which allows Windows Excel to properly read Mac spreadsheets. See the following for more info on this and how to set the origin in Excel: http://support.microsoft.com/default.aspx?scid=http://support.microsoft.com:80/support/kb/articles/q180/1/62.asp&NoWebContent=1 --- Date: Wed, 19 Nov 2003 16:33:51 +0000 (GMT) From: Prof Brian Ripley <[EMAIL PROTECTED]> To: Heiko Schaefer <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Subject: RE: [R] ISOdate returns incorrect date? Well, one clue is that date is before the modern era, and most OSes only go back to 1902. Some only go back to 1970! I suspect the OS does not know that 1900 was not a leap year. On Wed, 19 Nov 2003, Heiko Schaefer wrote: > > Does this really work for you? I still get: > > ISOdate(1900,6,16) > [1] "1900-06-15 14:00:00 Westeurop�ische Sommerzeit" > > ISOdate(1900,6,16,tz="") > [1] "1900-06-15 12:00:00 Westeurop�ische Sommerzeit" > > Obviously the time son influences the time, but it can > Not possibly account for the difference of a full day?! > > Still puzzled... > > Heiko -- Brian D. Ripley, [EMAIL PROTECTED] 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 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
