Welcome to the SYMPHONY Version 5.1.1 user's manual. Whether you are a new user or simply upgrading, this manual will help you get started with what we hope you will find to be a useful and powerful framework for solving mixed-integer linear programs (MILP) sequentially or in parallel. The subroutines in the SYMPHONY library comprise a state-of-the-art MILP solver with a modular design that makes it easy to customize for various problem settings. SYMPHONY works out of the box as a generic MILP solver that can be invoked from the command line, through an interactive shell, or by linking to the provided callable library, which has both C and C++ interfaces with a look and feel similar to that of other popular solvers (see Sections 6.1 and 6.2 for the library routines). Models can be read in MPS or GMPL (a subset of AMPL) format, as well as by interfacing with more powerful modeling environments, such as FlopC++ (also provided with the distribution). To develop a customized SYMPHONY application, various callbacks can be written and parameters set that modify the default behavior of the algorithm. Section 3.4 contains an overview of the API for these subroutines. Files containing function stubs are provided with the distribution.
SYMPHONY can be built on almost any platform and can be configured either for serial computation or in a wide variety of parallel modes. The parallel version can be built for either a fully distributed environment (network of workstations) or a shared-memory environment simply by changing a few configuration options (see Chapter 2). To run in a distributed environment, the user must have installed the Parallel Virtual Machine (PVM), available for free from Oak Ridge National Laboratories. To run in a shared-memory environment, the user must have installed an OpenMP compliant compiler (gcc 4.2 is currently the only compiler tested and fully supported).