Department Mathematik



Software by O. Forster:


ARIBAS is an interactive interpreter for big integer arithmetic and multi-precision floating point arithmetic. It has a syntax similar to Pascal or Modula-2, but contains also features from other programming languages like C, Lisp, Oberon. In ease of use it is comparable to Basic.

ARIBAS is used for the examples of number theoretic algorithms in the book Algorithmische Zahlentheorie by O. Forster.

ARIBAS can handle integers up to 64000 decimal places and floating point numbers with a precision up to 5120 bits.

It has several builtin functions for algorithmic number theory like gcd, Legendre and Jacobi symbol, Miller-Rabin probabilistic primality test, factorization algorithms (Pollard rho, elliptic curve, quadratic sieve), square roots modulo p, direct support for arithmetic in finite fields of characteristic 2, vector operations, builtin data type stack, etc.

ARIBAS is distributed under the GNU general public license.

There are versions of ARIBAS for UNIX-like systems (LINUX, MacOSX) and for MsWindows (Windows XP or higher).

ARIBAS can be downloaded here:



The file    aritut.txt    contains a short tutorial as an introduction to ARIBAS
The file    aridoc.txt    is a more systematic documentation of ARIBAS
Both files aritut.txt and aridoc.txt are pure ASCII files
The file    is a zip-file which contains both aritut.txt and aridoc.txt

Lehre/Teaching    Bücher/Books    Eprints

Otto Forster 2019-01-04