Note on Java Numerics

[walsteraEng.Sun.COM]

Jerome,

I enjoyed your note on Java Numerics, and agree with the arguments and the
conclusions you make in it.  Why isn't interval arithmetic the ideal
framework within which to deal with all the issues you raise concerning
numeric accuracy on alternate platforms?  In the proposed Fortran 2000
standard, there is one and only one requirement regarding interval accuracy:
"containment".  Interval results MUST contain the correct answer.  How a
processor achieves this or how "sharp" (or narrow) the containing interval,
is processor dependent, as you aptly point out, it must be.

In case you have not seen it, I refer you to the interval home page and the
draft standard contained therein.  Also, note the existing proposal for
support of intervals in Java.

	http://cs.utep.edu/interval-comp/main.html
	http://interval.usl.edu/F90/f96-pro.asc
	http://cs.utep.edu/interval-comp/java.html

Regards,

Bill Walster,
Manager, Fortran Compiler Technology and Russian Projects
SunSoft