Leading Math Software Undaunted by the Coming Year
2000or Even by the Year Two Billion
Computer industry experts predict dire consequences at the beginning of
the Year 2000the year many computer programs are expected to lose
their ability to manipulate and calculate dates properly, fatally
confused by the change of century. Projections of the problem's impact
on business, including a recent cover story in Newsweek magazine,
range from the grim to the cataclysmic. The only pleasant prospect is
for computer programmers, many of whom may need to be hired for
emergency software repairs.
However, the million scientists, engineers, educators, and students who
use Wolfram Research's Mathematica, the leading technical
computing system, have nothing to fear as January 1, 2000, approaches.
"We have thought a little further ahead," said Wolfram Research
President/CEO Stephen Wolfram, who earned a doctorate in theoretical
physics from Caltech at age 20. "Mathematica stores dates and
performs calendrical calculations using an arbitraryprecision
mixedradix representation that avoids the Year 2000 problem completely. We don't
anticipate any problems with our calendar algorithms until a
considerable time after the sun has burned itself out."
"For example," Wolfram explained, "according to Mathematica, the
year two billion A.D. begins on a Saturday, barring any intervening
modification to the calendar. There is also a more general result, which
says that any year A.D. which is a multiple of 2000 also begins on a
Saturday. That will always allow an extra working weekend for
programmers who don't use our product."
The Year 2000 question is only the most visible example of a larger
problem concerning how computers treat numbers. Nearly all software that
handles numbers makes certain assumptions about each number's size. This
means that date calculations are not the only ones subject to potential
"numerical overflow."
Imagine a business, for example, wanting to make a halfmilliondollar
sale to Russia. At current exchange rates, the number of rubles in a
halfmillion dollars is very close to overflowing the range of the
32bit signed integer, a very common data size.
Mathematica, however, is not bound by the limitations of
fixedsize integer representation. The same precise numberhandling
capability used by the calendar routines also allows it to multiply
numbers with hundreds of digits without the danger of numerical
overflow.
