a general purpose abstract, and a call for digest editors

[David Hough]

It has been suggested that the discussions on the numeric-interest list 
would be of interest in other media such as newsgroups and printed newsletters,
if they were suitably condensed and edited.  I don't particularly want
to take on such a responsibility, but I would like to hear from anybody
that would.   I would be glad to mail the accumulated postings so far to
anybody eager to begin the task.

In an effort to produce a general-purpose reusable abstract of
some current issues, I came up with the following:

	Mathematical Software in Standard C: why no Standard Results?

With the benefit of an ANSI Standard C programming language and an
ANSI/IEEE Standard for Binary Floating-Point Arithmetic, naive users
might expect that programming environments conforming to both standards
would produce identical numerical results.  More experienced
programmers would be able to "prove" that such results are technically
unfeasible, uneconomical, and undesirable.

What's a realistic expectation?  There are genuine mathematical issues
relating to elementary transcendental functions, performance issues
relating to systems that compute anonymous intermediate results in
extended precision, and philosophical issues relating to
standardization: what should be standardized and when, for
standardization suppresses innovation, both good and bad.  These issues
are aggravated if exception handling is also standardized: what was
cheap and convenient on simple computers may be exceptionally costly on
high-performance systems, and the cost may be payable even by programs
which generate no interesting exceptions.

The Numerical C Extensions Group faces such questions among many others
as it seeks to extend ANSI Standard C to a language for mathematical
software that is superior to Fortran-77 in every respect.  In NCEG
discussion, everybody claims to represent "the users" - the producers
and consumers of mathematical software.  But this user community
encompasses a variety of divergent views: what do users say they want?
what do they really want?  what would they want if they understood the
issues as the NCEG members do?  what would the NCEG do want if they
understood the issues as the users do?