# Links

Também disponível em: Português

A collection of *links* that you may find useful. Feel free to
suggest any link that is not present here or some description for
those who already are!

## Math

- Digital Library of Mathematical Functions: Electronic equivalent of the classic book Abromowitz and Stegun (apparently, the book is in the public domain, and there is also an electronic version here).

## Physics

- Collection of conventions, definitions, identities and useful formulas for general relativity (by Robert A. McNees)
- Simulating extremal spacetimes (SXS): collaborative research for understanding the physics of compact objects.

## Software

### Text editing

### Programming languages

- Emacs Lisp: List dialect used as extension language of Emacs.
- Guile: GNU implementation of Scheme programming language.
- Ruby: dynamic, simple and flexible language.
- Python: similar to Ruby. While not my preferred language, it may be more beginner friendly and, in addition to the large number of packages, it is the language used in the main programs I use (computer algebra).
- Cadabra: for tensor computer algebra, usually found in field theory.
- SageMath: general purpose computer algebra system.
- SageManifolds: SageMath extension for tensor calculus and differential geomnetry.