PresolveOpb

PaPILO integration with Pseudo-Boolean Problem instances of filetype .opb. File format is described here: http://www.cril.univ-artois.fr/PB16/format.pdf

Dependencies

papilo library. Update paths in CMakeFiles.txt before building. papilo also requires TBB, refer to https://github.com/lgottwald/PaPILO for more information.
Standard location for papilo is <project_root>/papilo. If your papilo is located in another folder, change location in CMakeLists.txt

To build

mkdir build 
cd build 
cmake ..
make

Binary usage

All Options

All options:
  --help                Display all options
  -I [ --filein ] arg   Path to file in (.opb)
  -O [ --fileout ] arg  Path to file out (default <file-name>.pre.opb
  --postsolve           Postsolve solution. Supply .postsolve file and solution
  -P [ --postfile ] arg Path to postsolve file (default 
                        <file-name>.pre.postsolve

Presolving

Presolve an instance by

./PresolveOpb -I <file-in>

Postsolving

Supply your solution along with the postsolve file.

./PresolveOpb -I <solution> -P <postsolve-file> --postsolve

Solution format

Currently only supports RoundingSat solution format. If you use RoundingSat pipe the solution to a file and supply that file.

Example workflow with RoundingSat

1. run ./PresolveOpb -I example.opb -O example.pre.opb
2. run ./roundingsat example.pre.opb --print-sol=1 > example.pre.sol
3. run ./PresolveOpb -I example.pre.sol -P example.pre.postsolve --postsolve

Changing Presolver Settings

The solver reads the settings from parameters.opb.txt. Settings can be changed there. Note that there are a few settings that might break .opb instances, these are marked in the parameters file.