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S-PLUS and Year 2000 Compliance
S-PLUS 4.x (standard & Professional) for Windows is fully year 2000 compliant.
For S-PLUS 3.3 for Windows, S-PLUS 3.4 for UNIX, and MathSoft StatServer, dates past the year 2000 are handled correctly internally. However, the print methods used do not display them correctly. The functions affected are 'dates()', 'seq.dates()', and 'chron()'. These routines have been changed in our development code base and will be included in the next releases of these products.
In the interim, there is a workaround for the year 2000 printing formats. It focuses on using the 'dates()' function in S-PLUS to generate dates beyond the year 2000. The key to doing this involves the function's "format=" argument. If the format does not include the complete four-digit year (and the default format does not), then when the 'dates()' calculation gets to 99, the display printed to the screen simply rolls over to 100.
This leads to the printing of odd "dates", as the following example shows:
dates(100,origin=c(month=12, day=20, year=1999))
[1] 03/29/100
If instead you specify a format that uses the complete year, you will get the correct date back:
dates(100, format="month day year", + origin=c(month=12,day=20,year=1999))
[1] March 29 2000
In both cases, computations such as time differences between two dates will be handled correctly, since S-PLUS performs all calculations using Julian dates. However, reports printed using the second format will be much easier to understand and interpret. |
Updated:
99/11 |
