POSTS

Tex Hour Agenda

Summary

This post covers a lot, quickly. Here's a table of contents.

  • Report: Last week Accessible Mathematics; video recording.
  • Discussion: This week (today) Input, Conversion and Output; LaTeX, Python docs, RST; everything to everything, Pandoc, Metcalfe's Law.
  • Teaser: Next week Archival Documents and Software; Knuth on Future of TeX and Metafont (1990).
  • Preview: Next month, monthly cycle; B, A, C, D and X; Why B before A?

Last week Accessible Mathematics

Accessible mathematics was last week's topic. It was a special TeX Hour in several ways. Over 20 people came, people got to know each other, and important topics were discussed. Several of the participants were blind users of TeX, and they described their experience and problems. I suggested we have another similar meeting not next month, but in April or May.

Here are some posts from last week.

Video recording

Last week's meeting was the first to be recorded. I gratefully acknowledge funding from the UK TeX Users Group. They're paying for 3 months of a Zoom license, so that I can record the meetings on the cloud. For clarity, the TeX Hour is not a UK TUG event.

The first 20 minutes of this TeX Hour was the participants introducing themselves to each other. This by itself is fascinating, and well worth listening to. There's such a diversity of experience and interests shown.

TeX Hour: Accessible Mathematics: 11 Feb 2021 (YouTube)

This week Input, Conversion and Output formats

Input, conversion and output formats will be the topic this week (today, 6:30 to 7:30pm UK time). The zoom details are on the contact page. I'm not expecting more than 5 or 10 people, because I've not had time to publish interesting blog posts.

There seem to be two architectures. The first is A -> B, A -> C, A -> D etc. The second is X -> Y, for all values of X and Y. I'll explain

LaTeX to everything

We write are documents in LaTeX (or some other TeX markup language). And so for LaTeX authors the useful conversion tools are

  • LaTeX to PDF (of course)
  • LaTeX to HTML (of course)
  • LaTeX to XML (for those that like it)
  • LaTeX to everything

Python docs

The Python docs used to be written in LaTeX, and converted to HTML for web use. This was done using a customising the best tool then available. This starting point was LaTeX2HTML, developed by Nikos Drakos in 1996.

Now, RST to everything

LaTeX2HTML worked well for a long time. But as the Python community grew, then wanted more, so they moved house. For good reason the Python Documentation Special Interest Group wanted

a markup syntax and toolset to allow auto-documentation, where the docstrings of Python systems can be extracted in context and processed into useful, high-quality documentation for multiple purposes.

And so the Python community made a big effort to develop and switch to a new format ReStructured Text (RST). For background PEP 287 – reStructuredText Docstring Format.

And now the Python conversion tools are

  • RST to LaTeX (and hence PDF)
  • RST to HTML
  • RST to EPUB
  • RST to plain text

Now, everything to everything

Notice that now LaTeX is both an input format (for heavy mathematics and other purposes) and an output format (for the Python docs). And there are other examples. Sometimes XML is an input format. Sometimes it's an output format.

This makes Pandoc very interesting. So far as I know, it's the most widely used text-based conversion system for which the social value is proportional to square of the work put into it.

The creator of Pandoc spoke at last year's TUG conference. TUG 2020: John MacFarlane: Pandoc for TeXnicians (YouTube).

Phones, faxs, network effect, Metcalfe's law

A telephone is useful only if you know someone else who has a telephone. And if you do, they can call you and you can call them. The same goes for fax machines.

These are examples of the Network effect (wikipedia) and of Metcalfe's Law (wikipedia), which states

the value [to society] of a telecommunications network is proportional to the square of the number of connected users of the system ($n^2$)

If our phone network use the A -> B, A -> C, A -> D architecture then its economic cost is proportional to $n^2$. In other words, social value and economic cost are proportional.

But local phone networks use an eXchange, which I'll denote by X. And now our phone network need only have lines A -> X, B -> X and so forth. And now the social value is proportional to the square of the economic cost.

Hence my statement about pandoc.

Next week, Archival Documents and Software

Being archival is core quality and value of TeX. In 1990 Don Knuth announced

TeX development is at an \end.

My work on developing METAFONT, and Computer Modern has come to an end. I will make no further changes except to correct extremely serious bugs.

TeX is public domain, same across space

I have put these systems into the public domain so that people everywhere can use the ideas freely if they wish. I have also spent thousands of hours trying to ensure that the systems produce essentially identical results on all computers.

Fixed points have great value

I strongly believe that an unchanging system has great value, even though it is axiomatic that any complex system can be improved. Therefore I believe that it is unwise to make further “improvements” to the systems called TeX and METAFONT.

Same across time

Let us regard these systems as fixed points, which should give the same results 100 years from now that they produce today.

All these quotes are taken from Don Knuth: The Future of TeX and Metafont (1990), (PDF)

Next month

The TeX Hour is settling into a monthly cycle. All meetings are Thursday 6:30 to 7:30pm UK time, and are on Zoom.

  • First Thursday: Beginners (to math and to whole documents)
  • Second Thursday: Accessibility (with a focus on math)
  • Third Thursday: Conversion (including typesetting)
  • Fourth Thursday: Durability (of documents and software)

And in April, July, September and December this year we have

  • Fifth Thursday: X (explore, experiment, expand, the unknown)

This cycle will persist for as long as it's useful, and there's nothing better.

A TeX alphabet for the monthly cycle

By design the initial letters for the monthly cycle are A, B, C, D and X. In other words, an alphabet, similar to “A is for Apple” and “B is for Ball”. Here goes:

  • A is for Accessibility
  • B is for Beginners
  • C is for Conversion
  • D is for Durable (and Document)
  • X is for eXplore, eXperiment, eXpand and the unknown

Why B before A?

Even though Accessibility comes before Beginners, the monthly cycle is B, A, C, D and perhaps X. Why? Here are some reasons.

  1. The start of a story at the beginning. (And \begin is a LaTeX command.)

  2. Accessibility means that some object is accessible to someone. We need an object and a user. Then we ask the user: Can you access the object?

  3. I think that saying “person with disability” is more respectful than “disabled person”. It reminds me that a person is a person, even if they have a disability.

  4. I think B, A, C, D works better as a monthly cycle.

Thank you

Thank you for reading to the end of this long post. I hope that it's done no harm, and that some of it helps someone somehow.