CBC
Introduction
CBC is a high-performance open source mixed integer programming solver. It implements branch-and-cut algorithm, supports reading and writing LP and MPS standard format model files, reading and solving NL format model files, and also provides C and C++ and other high-level language programming interfaces.
The main developer of CBC is John j. Forrest, whose development language is C++ and is released as open source under the Eclipse Public License 2.0. Currently, it is mainly maintained by John J. Forrest, Ted Ralphs and others.
Parameters
Termination condition
| Parameter | Description |
|---|---|
| allow(ableGap) | Stop when gap between best possible and best less than this |
| ratio(Gap) | Stop when gap between best possible and best known is less than this fraction of larger of two |
| integerT(olerance) | For a feasible solution no integer variable may be more than this away from an integer value |
| sec(onds) | Maximum seconds |
| maxIt(erations) | Maximum number of iterations before stopping |
| maxN(odes) | Maximum number of nodes to do |
Print log
| Parameter | Description |
|---|---|
| log(Level) | Level of detail in Solver output |
Algorithm
| Parameter | Description |
|---|---|
| presolve | Whether to presolve problem |
| preprocess | Whether to use integer preprocessing |
| cuts(OnOff) | Switches all cut generators on or off |
| heur(isticsOnOff) | Switches most primal heuristics on or off |
| node(Strategy) | What strategy to use to select the next node from the branch and cut tree |
| threads | Number of threads to try and use |
Input and output results
mips(tart)Reads an initial feasible solution from filesolu(tion)Prints solution to file
| Parameter | Description |
|---|---|
| mips(tart) | Reads an initial feasible solution from file |
| solu(tion) | Prints solution to file |
For details about the parameters, see: https://github.com/coin-or/Cbc (opens new window)
Examples of Usage
Solve LP/MPS files
Assuming that the test example is test.mps, the Cbc command line is used to solve the problem, the time limit is 60 seconds, the number of threads is 2, and the output result file is test.sol, then the calling command is:
cbc test.mps sec=60 threads 2 solve solution test.sol
Solve NL files
Assuming that the test example is test.nl, the time limit is 60 seconds, and the log is enabled, then the calling command is:
cbc test.nl -AMPL "log=1 sec=60"