The dBase format is pretty common among GIS files, (it's used in
ESRI Shape files and the MapInfo .DAT file is a dBase file, and
commonly seen in MS Access and Excel hangouts) but in a dBase
file header there are only 3 bytes for the creation date,
arranged as year, month and day (bytes at offsets 1, 2, and 3
from the start of the file). I set my computer's date ahead to
June 4, 2000, and when I created these sorts of files with the
above mentioned software these bytes indicate a date of 100/6/4.
This says in effect that we are in the year 100 of the 20th
century, and not year 0 of the 21st century. As long as you apply
one or the other convention consistenly you get the right date,
but woe to those whose software components mix them! So my
question is what's the right way to treat these?

Should the June 4, 2000 date be 00/6/4 or 100/6/4? To get the
former, you have to test to see if the year is >= 2000 and less
than 3000 then subtract 2000 from the year. If it's
1900-something, you subtract 1900. Anyway, is there a convention
yet for how these should be treated?

- Bill Thoen
----------------------------------------------------------------------
To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put
"unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]

Reply via email to