SoPlex is an optimization package for solving linear programming problems (LPs)
based on an advanced implementation of the primal and dual revised simplex
algorithm. It provides special support for the exact solution of LPs with
rational input data. It can be used as a standalone solver reading MPS or LP
format files via a command line interface as well as embedded into other
programs via a C++ class library. The main features of SoPlex are:

* presolving, scaling, exploitation of sparsity, hot-starting from any regular
  basis
* column- and row-oriented form of the simplex algorithm
* an object-oriented software design written in C++
* a compile-time option to use 80bit extended ("quad") precision for numerically
  difficult LPs
* an LP iterative refinement procedure to compute high-precision solution
* routines for an exact rational LU factorization and continued fraction
  approximations in order to compute exact solutions.

WWW: http://soplex.zib.de