# Re: integrals

• To: math-font-discuss@cogs.susx.ac.uk
• Subject: Re: integrals
• From: alanje@cogs.susx.ac.uk (Alan Jeffrey)
• Date: Fri, 13 Aug 93 18:43 BST

>I'll strongly recommend that the MFG members take a look at the
>following books, unless of course they'd rather create a
>"TeX for poets".

If we're into recommending books, can I recommend almost anything
written by Peter Johnstone, for example Stone Spaces' (CUP, 1982).
An excellent book, and by an author who cares about the appearance of
his books.  In general, most books in the CUP Cambridge studies in
advanced mathematics' series are very well-produced.  Also worth a
look is Sanders Mac Lane's Categories for the Working Mathematician'
(Springer-Verlag, 1971).  I just wish I could find some theoretical CS
books that were as well-produced...

>Instead of the obvious way of typing a formula like
>${\bf\tau}={\bf r}\times{\bf F}$,

In plain TeX + DC + new math with bold, it'll be:

${\bf\tau}={\bf r}\times{\bf F}$

In LaTeX2e + DC + new math with bold, running under compatibility mode
with LaTeX2.09, it'll be:

${\bf\tau}={\bf r}\times{\bf F}$

These will produce the same results they do at the moment, namely a
non-bold $\tau$, a bold r and a bold F.  Similarly, the input
${\bf\Gamma}$ will produce a bold $\Gamma$.

There is a related question of what the LaTeX2e syntax should be
without compatibility mode, which is another matter...

In order to achieve this, the lower case Greek can be made of type
Ord, and the upper case Greek of type Variable.  Then \bf sets the
\fam to be an MC-encoded font containing bold upright Latin, and bold
upright and slanted Greek.  This font can be demand-loaded, since
there are no \mathchardef's pointing to it.

One advantage of the new encoding is that it makes it possible for
macro-writers to redefine the lower case Greek control sequences
\alpha...\omega to be of type Variable, so that the only distinction
between Greek upper and lower case is that the former is upright and
the latter is slanted.  Alternatively, macro writers may choose to have
the default upper case Greek slanted as well.  Or they might both be
upright, or...

At the moment, if a user types ${\bf\mu}$ as you suggested, they will
get a non-bold $\mu$.  Under the new encodings, with suitable fonts
and macro definitions, ${\bf\mu}$ will produce a bold $\mu$.

>I am curious as to how many members of the MFG have a background
>in math, physics or engineering.

My background is theoretical computer science, but so theoretical that
I wouldn't be recognized by most people!  And if you want an example
of a community which uses each and every glyph in every style going,
you should try CS.  You didn't mention the use of \tt in math mode,
for example...

>I wish members of MFG could see that most people who use TeX are
>not "TeX-hackers".

We are very well aware of that.  We are currently considering the
low-level detail of font encodings.  Because of this, the discussion
will inevitably be very technical at times.  However, we are very
aware of the large user community of TeX, and we are striving to
ensure that TeX will continue to be the typesetting system of choice
for technical material.  The discussion on this group will continue to
be very TeXnical, because sentences like \Gamma can be
\mathchardef'ed to be of type Variable' are clearer and less likely to
be misunderstood by this group than \Gamma can be defined to be a
single math character whose style changes with plain TeX commands like
\bf and \sf.'

>They simply want to write a paper or a book
>without having to deal with all sorts of idiosyncracies.

Part of the aim of the MFG is to iron out many of the current
inconsistencies of TeX (such as having to treat \gamma and \Gamma
differently).

>A little common sense never hurts. Or shouldn't.

I wondered what that nagging ache in my foot was, it was some common
sense that had gotten into my shoe somehow :-)

Alan.

`