# Paraffinalia free software

The software packages available here have been developed for use in various engineering and scientific calculations. All are released under the GNU General Public License so they are free (as in freedom) software with absolutely no guarantee or warranty. It is your responsibility, as with all numerical software, to satisfy yourself that a code, and its inputs, are giving answers you are prepared to rely on. The codes are documented, in the form of HTML pages describing the basic structure of the libraries and the functions in them. This documentation is installed when you install the packages.

The main package is BEM3D which is a library and associated tools for boundary element calculations. Meshing and visualization are performed using GMSH and the tools include programs for acoustic scattering and radiation, and a panel method for deforming bodies. It also interfaces to GMC to give it some (not very) fast multipole capability, although it does greatly increase the number of elements it can handle.

The tools in BEM3D use SISL, a Simple Iterative Solver Library, to solve the matrix equations, and WMPI, Wrapper for MPI, to allow the same source code to be used on both serial and parallel systems. You will probably not want to use them for anything other than installing and running BEM3D but it is always possible you can find some use for them.

There are two other, stand-alone, libraries provided here. The first generates Gaussian (type) Quadrature Rules, mainly intended to be used in boundary integral problems with singular or hypersingular kernels. The second is a General Tetrahedralized Volume library for three-dimensional volumes formed of tetrahedra, which offers functionality similar to that of GTS, including Delaunay tetrahedralization of arbitrary point sets.

## Other software

The codes you will find here depend on a number of packages produced by other people and you will need to install some or all of them in order to use the software here. These packages are:

- GMSH for meshing and visualization.
- the GNU Scientific Library.
- the GNU Triangulated Surface library for geometry handling.
- the Matheval library for function evaluation.
- LAPACK for linear algebra.
- A Basic Linear Algebra System such as the the Netlib or ATLAS implementation.