Here I comment on my intertwining with computers.
(This page is seldom updated, sorry.)
is an operating system
(a free clone of Unix).
It was originally created by
and has been developed with the collective effort
of many volonteers around the world.
I strongly adhere to this philosophy!
Frankly, I don't remember the last time
I had a Windows operating system installed in my computer.
TeX and LaTeX
is an outstanding language,
devised to produce high quality typesetting,
including mathematical text.
wonderlang in 1987 through the LaTeX door
(writing my degree thesis using a popular wysiwig program
had been an unfortunate experience).
Useful information about TeX can be retrieved from the
TeX Users Group home page;
see also the
Comprehensive TeX Archive Network.
LaTeX is nowadays the standrd set of TeX macros.
Since it is a bit tight,
one of my first tasks was to give some flexibility to the "document styles",
which years ago didn't possess elementary features such as
chosing if you want your references to be called
"Bibliography", or "Bibliografia"...
A later version of LaTeX has included most of this flexibility,
mainly due to the Babel project.
I also wrote a file containing hyphenation patterns for Catalan.
Other people wrote similar files,
and I don't know if they have been unified.
In any case you can
at the home page of the (not very much alive) Catalan TeX Users Group,
Tirant lo TeX.
Another problem I worked on is the Catalan double ell
that appears in words like xarel·lo.
I wrote macros for producing a typographically pleasant middle dot;
perhaps they should be slightly improved,
but you can find them
(it is only 15 lines of TeX code).
I also wrote some macros to draw commutative diagrams,
to deal with derivatives,
to number equations in special ways, ...,
and many more,
but nowadays there are better solutions somewhere in the web.
Fortunately, those times when drawing graphics on a LaTeX document was painful passed away.
allows you to write LaTeX-like code to produce beautiful graphics.
While trying to improve my TikZ,
TikZ pour l'impatient
I have collected some of my usages of TikZ in
has become one of my favourite sources of information
I have written and edited several pages, mainly for the
At a certain point,
I was fed-up with the despotic behaviour of some administrators,
so nowadays my collaboration is only occasional.
is a program for performing symbolic mathematical computation,
designed at the University of Waterloo
some years ago.
The mathematics courses at the Telecommunication School
included from 1992 to 2009 laboratory sessions with Maple.
I was largely involved with them;
I even dared to produce a booklet (1998) about Maple
for the course on
Maple can also be useful to compute Lie brackets in 8-dimensional spaces...
More recently, I used Maple to study models for the vibration of rigid strings and their application to piano tuning.
Occasionally I have used other computation systems like Matlab, Mathematica, SageMath, Minitab...
The last one,
(HyperText Markup Language)
is the language used to compose pages for the World Wide Web (WWW)
--as this one.
This language and the web as we know it were devised at the
in late 1990
I learned some HTML in order to create the
of my research group in 1997.
Of course, writing raw HTML is not especially difficult
if you know TeX previously.
PostScript is a page description language invented by
some years ago.
Though PostScript is not intended for humans,
learning something about it may be fun and interesting.
(Do you know what is reverse Polish notation?)
Years ago I devised some simple macros to draw circuits
that were useful for some colleagues.
Nowadays this is useless!
You can find some information about PostScript
at the home page of
you can also look at
A First Guide to PostScript
sometimes dubbed as
pathologically eclectic rubbish lister,
is a postmodern programming language,
I learned some about Perl, and the CGI library
to program some forms for the web page of the year 2000 session of the
Fall Workshop on Geometry and Physics,
as well as to publish its proceedings.
Some resources are
Comprehensive Perl Archive Network.
Nowadays I wouldn't be able to program in Perl,
nor in other languages that I learned far more time ago,
like Fortran or Cobol.
The notable exception could be