RFC 1003 (rfc1003) - Page 2 of 7

Issues in defining an equations representation standard

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