7.1 Advantages

GiNaC has several advantages over traditional Computer Algebra Systems, like

• familiar language: all common CAS implement their own proprietary grammar which you have to learn first (and maybe learn again when your vendor decides to `enhance' it). With GiNaC you can write your program in common C++, which is standardized.
• structured data types: you can build up structured data types using structs or classes together with STL features instead of using unnamed lists of lists of lists.
• strongly typed: in CAS, you usually have only one kind of variables which can hold contents of an arbitrary type. This 4GL like feature is nice for novice programmers, but dangerous.
• development tools: powerful development tools exist for C++, like fancy editors (e.g. with automatic indentation and syntax highlighting), debuggers, visualization tools, documentation generators…
• modularization: C++ programs can easily be split into modules by separating interface and implementation.
• price: GiNaC is distributed under the GNU Public License which means that it is free and available with source code. And there are excellent C++-compilers for free, too.
• extendable: you can add your own classes to GiNaC, thus extending it on a very low level. Compare this to a traditional CAS that you can usually only extend on a high level by writing in the language defined by the parser. In particular, it turns out to be almost impossible to fix bugs in a traditional system.
• multiple interfaces: Though real GiNaC programs have to be written in some editor, then be compiled, linked and executed, there are more ways to work with the GiNaC engine. Many people want to play with expressions interactively, as in traditional CASs. Currently, two such windows into GiNaC have been implemented and many more are possible: the tiny ginsh that is part of the distribution exposes GiNaC's types to a command line and second, as a more consistent approach, an interactive interface to the Cint C++ interpreter has been put together (called GiNaC-cint) that allows an interactive scripting interface consistent with the C++ language. It is available from the usual GiNaC FTP-site.
• seamless integration: it is somewhere between difficult and impossible to call CAS functions from within a program written in C++ or any other programming language and vice versa. With GiNaC, your symbolic routines are part of your program. You can easily call third party libraries, e.g. for numerical evaluation or graphical interaction. All other approaches are much more cumbersome: they range from simply ignoring the problem (i.e. Maple) to providing a method for `embedding' the system (i.e. Yacas).
• efficiency: often large parts of a program do not need symbolic calculations at all. Why use large integers for loop variables or arbitrary precision arithmetics where int and double are sufficient? For pure symbolic applications, GiNaC is comparable in speed with other CAS.