The PPRN package was developed in the Statistics and Operations Research Dept. at Universitat Politecnica de Catalunya, Barcelona (Spain), by Jordi Castro and Narcís Nabona. The package is appropriate for solving single/multicommodity network flow problems with linear/nonlinear objective function and with/without linear side constraints. Thus it can be viewed as a general package for solving a high variety of network flow problems (though it was originally designed for solving nonlinear multicommodity problems with side constraints).

The code has been tested comparing its performance against other codes. When solving pure linear network flow problems, it has proved to be faster than alternative codes like NETFLO (J. Kennington) or RELAX-IV (D. Bertsekas) in all cases tried of a battery of dimacs problems. When solving linear multicommodity problems its performance was in general better, though not in all the cases tested, than that of MCNF85 (J. Kennington). For nonlinear problems it has only been compared with general purpose packages like MINOS (Murtagh and Saunders) and PPRN always outperformed it.

• To know more about how to use the package, please read the user's guide document (DR 94/06).

• This technical report (DR 94/02) presents some computational results of PPRN in the solution of linear multicommodity problems.

• This technical report (DR 94/05) presents some computational results of PPRN in the solution of nonlinear multicommodity problems.

• This paper describes the main features of the algorithm described in PPRN.

You can only use the package for academic purposes. For other types of usage, please contact with the authors sending a message to jordi.castroupc.edu.

PPRN is available in object form (no source code is provided). We have precompiled libraries for the following architectures (note that all these files are gzipped libraries, so yo have to gunzip them):

• libpprn.a.SUN-SOLARIS : library created with compiler options "-fast" for C and Fortran files.

• libpprn.a.OSF1-AXP (DEC-Alpha): library created with compiler options "-fast" for Fortran files and "-std1 -O4 -Olimit 700" for C files.

• libpprn.a.HP-UX9.03 (HP9000/720): library created with compiler options "-O" for Fortran files and "-Aa -O" for C files.

• libpprn.a.R6000-AIX3.2 (IBM R6000): library created with compiler options "-O3"

• libpprn.a.Linux32: library for 32 bits platforms created with gcc and g77 2.95.2 with compilers options "-O3". The executable must be compiled with g77.

• libpprn.a.Linux64: library for 64 bits platforms created with gcc 4.0.2 with compiler options "-O3".

• libpprn.a.Linux64gfortran: library for 64 bits platforms created with gcc and gfortran (not g77) 4.3.2 with compiler options "-O3".

• zip file with pprn.dll and pprn.lib: Windows-Xp 32 bits dll and lib file, release version created with Compaq Visual Fortran and Microsoft Visual C++ 6.0.

Once you got and gunzip the appropriate file, rename it as libpprn.a. Remember to run "ranlib libpprn.a" after copying the library to the directory in your machine (when necessary).

If you have a different architecture from those currently available, please contact us at jordi.castroupc.edu.

Follow these steps to test PPRN:

• First move the library libpprn.a to the appropriate directory in your system.

• Get these files:
  • makefile to compile all the programs (you will likely need to adjust the variable DIRPPRN which must point to the directory were libpprn.a were installed).

  • lintest.f: fortran source file of a linear multicommodity example.
  • lintest.c: C source file of a linear multicommodity example (use it if the fortran file above doesn't work; modify makefile accordingly).
  • ltest.dat: data of the linear test.
  • ltest.spe: specification file with parameters for the linear test.

  • nolintest.f: fortran source file with the objective function of a nonlinear multicommodity example.
  • nolintest.c: C source file of a nonlinear multicommodity example (use it if the fortran file above doesn't work; modify makefile accordingly). It was obtained with the f2c fortran to C translator. You need to have installed f2c in you machine.
  • ntest.dat: data of the nonlinear test.
  • ntest.spe: specification file with parameters for the nonlinear test.

• Test PPRN with the linear problem:
  • To make the executable, type (after adjusting the makefile options): "make lintest"
  • To run the program, type: "lintest"
  • PPRN will write the file "ltest.lst", output file with the optimization process and solution found.

• Test PPRN with the nonlinear problem:
  • To make the executable, type (after adjusting the makefile options): "make nolintest"
  • To run the program, type: "nolintest"
  • PPRN will write the file "ntest.lst", output file with the optimization process and solution found.

If you have some comments or suggestions, or you find any trouble or abnormal situations when using the package, we would appreciate if you would send a message to jordi.castroupc.edu .