We hope that the table of contents will give a first idea about the intention of these pages: a collection of all kind of formulas and data which might be useful in the theory of automorphic forms or its applications. Moreover, and the most important, you can immediately apply almost all formulas interactively, or ask for an excerpt from the available data bases. The amount of available information will hopefully increase in course of time. The construction of this site is intended as a long-term project. Contributions, as well as hints to errors, are welcome.

These pages conform to the W3C Standard, so that it should be possible to view them with any browser. They were tested extensively with Opera 7.54. If you feel uncomfortable with the writing or the frames layout, please remember that you can (very likely) change the font or open the pages in separate windows. You need Javascript to be enabled, which, however, is probably the default behaviour of your browser.

A slightly technical note: The input fields of the various forms accept in general any sensible expression using the letters 0 1 2 3 4 5 6 7 8 9 + - * / ^ ( ) and space and comma, like e.g. (2^3*3 + 1)*5. Exceptions to this are explicitly marked. If, instead of a reasonable answer, you obtain strange error messages then please check again your input. Also, you are yourself responsable for the results, in the sense that, if you ask for the generating series of the dimensions of the spaces of modular forms of level 0 and obtain the answer 1, then it is your fault :-) For reasons of security, there are in general bounds for the possible input. This is hopefully not a problem since it is hard to imagine that someone will ever need the dimensions of modular forms of weight 171,000,000 + 1; but we would be very much interested to know if we are wrong.

These pages have been tested with Opera 7.54. Hence, using such a browser or an equivalent one, you should be able to withdraw all desired data without having to care about any technical detail. If you find bugs, or if you encounter problems using another browser, please send a message.

A strongly technical note: these pages are written using plain html 4.1, css stylesheets and javascript. The data are either calculated upon request by calling PARI/GP 2.2.10 and reading in suitable GP scripts, or else they are fetched from precalculated tables. To this end some cgi-scripts, written in Perl and C++, serve as "brokers".

The mathematical writing is admittedly poor. This is because the current versions of browsers do paradoxically not yet support mathematical writing, and we want to avoid the overhead which is usually implied be the different existing work-arounds. However, people talk already about MathML and it is very likely that it will become a standard soon; these pages will then eventually be updated.

Why the name MODI ? It is indeed easy to find good reasons for this choice: thor is the machine on which the development of this project started, and Modi is one of the sons of Thor (the norse deity) who will survive Ragnakor (the norse dooms day). Also, MODI can stand for Modular Objects Data Inteface ... if someone has a better proposition ? And last not least one may take it just as a simple minded allusion to the sounds of words like modular forms and interesting.

Happy modular forms surfing,

Nils-Peter Skoruppa, Bordeaux 1999 and Siegen 2005