RFC 1003 (rfc1003) - Page 2 of 7
Issues in defining an equations representation standard
Alternative Format: Original Text Document
RFC 1003 March 1987
include equations in messages.
A glance through any scientific journal will demonstrate the
importance of equations in scientific communication. Indeed, papers
in some fields seem to contain more mathematics than English. It is
hard to imagine that when people in these fields are connected into
an electronic mail community they will be satisfied with a mail
system which doesn't allow equations. Indeed, with the advent of
the NSF's Experimental Research in Electronic Submission (EXPRESS)
project, scientists will begin submitting manuscripts and project
proposals directly through electronic mail and the ability to handle
equations will be essential.
Currently, there exists no standard for the representation of
equations. In fact, there is not even agreement on what it is that
ought to be represented. Users of particular equation systems (such
as LaTex or EQN) sometimes advocate just including source files of
that system in messages, but this may not be a good long-term
solution. With the new NSF community coming on line in the near
future, I feel the time is now right to try to define a standard
which will meet the present and future needs of the user community.
Such a standard should allow the interchange of equations via
electronic mail as well as be compatible with as many existing
systems as possible. It should be as general as possible, but still
efficiently represent those aspects of equations which are most
commonly used. One point to be kept in mind is that most equations
typesetting is currently being done by secretaries and professional
typesetters who do not know what the equations mean, only what they
look like. Although this is mainly a user interface consideration,
any proposed standard must not require the user to understand an
equation in order to type it in. We are not interested here in
representing mathematics, only displayed equations.
In this memo, I will try to raise issues that will need to be
considered in defining such a standard and to get a handle on what
it is that needs to be represented. Hopefully, this will form the
basis of a discussion leading eventually to a definition. Before
examining what it is that could be or should be represented in the
standard, we will first review the characteristics of some existing
systems.
2. Existing Systems
There currently exist many incompatible systems which can handle
equations to a certain extent. Most of these are extensions to text
formatting systems to allow the inclusion of equations. As such,
general representation and standards considerations were not a major
concern when these systems were initially designed. We will examine
the three main types of systems: Directive systems, Symbolic
Language systems, and Full Display systems.
Katz