TeX


TeX pronunciation is a document composition software system widely used by scientists, particularly in mathematics , physics , bioinformatics , astronomy and computer science . TeX comes from τεχ , the beginning of the word τέχνη (“art, science”, in ancient Greek ), and is pronounced / tɛx / 1 or / tɛk /.

Origin and history

TeX was created in 1977 by the mathematician and computer scientist Donald Knuth , overwhelmed by the poor quality of typography of the time when he was preparing the second edition of The Art of Computer Programming .

From version 3, TeX used a system idiosyncratic of version numbering , updates are indicated adding an extra digit after the decimal point and approaching the version number asymptotically the number{\ Displaystyle \ pi}2 . The current version of TeX is 3.14159265, the latest update dated January 12, 2014 3 . The essential features of TeX have been fixed after version 3.0 , and all subsequent versions contain only bug fixes . Donald Knuth, while pointing out possible improvements, insisted that having a fixed system that will always produce the same output is more important than introducing new features 2 .

How it works

TeX interprets a formal document description language defined by D. Knuth (commonly, we do not distinguish between the TeX software and this language which is also called TeX ): in other words, it is not a text-formator To render immediately where the document in preparation appears on the screen as it is supposed to be when printed, but a software translating a textual description into a graphic document.

TeX therefore takes as input a document written in text mode with controls (most of which begin with an against backslash “\”) and creates a file format dvi containing a description of pages of text, that is, The positions of the characters on the page. TeX commands are used to choose the fonts to use, to add spaces … Some of the algorithms used by TeX are quite complex (for example, it reads an entire paragraph to decide where to cut lines).

The commands recognized by the TeX compiler are divided into “primitives” (there are about 300), and “macros”, created from the previous ones. The macros make possible quite complex structures (loops, conditions and et cetera) as well as the realization of calculations.

In order to simplify the preparation of a document, D. Knuth defined a set of about 600 macros called plain TeX which is described in his book The TeXbook together with primitives and internal mechanisms. This causes confusion between plain TeX and the TeX compiler. In order to speed up the creation of a document, this set of macros, called format , is precompiled.

Since the direct use of the plain TeX format is rather arduous, it has been extended to LaTeX (again, no distinction with the name of the language in which is described the document also known as LaTeX), written originally By Leslie Lamport , which is actually a set of macro-commands based on TeX. Other formats are also available, such as ConTeXt , AMS-LaTeX …

The characters themselves are created with Metafont .

Use

Recently [When?] , It is possible to use TeX to automatically generate the delicate layout of XML data. This allows the concatenation of syntactic differences between the two descriptive languages ​​using TeXML . We can therefore consider TeX as an alternative to XSL-FO in the context of XML publishing.

Extensions

The TeX compiler has been the subject of some extensions (not to be confused with formats like LaTeX , ConTeXt ), including:

  • PdfTeX : directly creates Portable Document Format files .
  • MlTeX : multi-lingual TeX .
  • TeX-XeT : supports writing from right to left.
  • VTeX : commercial compiler of MicroPress.
  • Omega : to process multilingual documents.
  • Epsilon-TeX : adds some primitives to TeX.
  • XeTeX : a Unicode version of TeX with modern font management .
  • LuaTeX : a Unicode version that has an interpreter for the Lua language .

Community

There are many user groups TeX / LaTeX in the world, which are usually related to language: GUTenberg (French), TUG (English, means TeX Users Group ), DANTE (German) CervanTeX (Spanish speaking) GUIT (Italian-speaking), NTG (Dutch-speaking) …

Some of these groups publish newspapers ( GUTenberg Cahiers , Letter GUTenberg , PracTeX , TUGboat …) and organize conferences, sometimes jointly ( EuroTeX …).

References

  1. ↑ ( in ) Donald E. Knuth, The TeXbook , Ch. 1: The Name of the Game, p.  1
  2. a and b ( in ) Donald E. Knuth. The future of TeX and METAFONT [ archive ] , NTG MAPS journal (1990), 489. Reprinted as Chapter 30 of Digital Typography , p.  571.
  3. ↑ ( en ) ” TeX source code header [ archive ] , listing the updates.