Precision
Abacus uses a mathematical tool called Taylor Series to determine values
as accurate as the user desires. Of course, this comes with some
performance issues with larger numbers. However, Abacus has been
tested to generate the value of e correctly to a thousand digits.
Configurable and Customizable
The very first idea for Abacus was inspired by how difficult it was
to program a TI-84 calculator. Only two languages were available, TI-BASIC
and Assembly, the latter having virtually no documentation. Determined
to be better than a TI-84, Abacus implemented a plugin system that allows
users to easily create and add plugins written in the same programming
language as Abacus itself - Java. These plugins can access the full
power of the language, and implement their own ways of handling numbers,
as well as their own functions and even operators.
Besides the ability to add plugins, Abacus also adds some general
options that can be used to make the user's experience more pleasant.
For instance, it allows for a computation limit to be set in order
to prevent excessively long evaluation: 8!!! is, for example, an expression
that even Wolfram Alpha doesn't compute accurately, and will never finish
on Abacus (it's simply too large). The computation limit will allow Abacus
to kill a computation if it takes too long. Support for user-definable
precision is also planned.
Built-in Documentation
Abacus plugins are given a mechanism to register documentation for
the functions that they provide. The Abacus GUI displays these
functions in a searchable list, allowing the user to read the parameters
that have to be supplied to each function, as well as learn about
its return value.
The search finds functions not only by their names, but also by relevant
terms mentioned in the function's description, thus allowing related
functions to be displayed together.