MakeMPS
| NLA |
|---|
| QRSlv |
| CMSlv |
| IPSlv |
| NLP |
| CONOPT |
| IPOPT |
| TRON |
| MINOS |
| Opt |
| NGSlv |
| DAE/ODE |
| IDA |
| LSODE |
| DOPRI5 |
| RADAU5 |
| LA |
| Linsolqr |
| Linsol |
| LP |
| HiGHS |
| MakeMPS |
| Logic |
| LRSlv |
MakeMPS is a 'solver' for ASCEND that exports an active MODEL to the [MPS file format https://en.wikipedia.org/wiki/MPS_(format)], with support for linear and mixed-integer programs (LP and MIP). The exported file can then be loaded and solved using an external program, such as highs or gurobi. It should then be possible to re-incorporate the solution back into ASCEND again when completed, although this part is currently untested.
The source code is available at solvers/makemps
Update: this solver was 're-commissioned' in 2026, with numerous updates following changes to the Solver API are required. Some sample problems have been added and exported in the CUnit test suite (see ascend/solver/test/test_makemps.c, and the code tests that the resulting problems are successfully solved.
Note that the MPS format is restricted to linear and mixed integer and linear programs. Another file format, supported by AMPL, is the .nl file format, which can also handle non-linear equations. It would be desirable to extend the current MakeMPS export code and implement support for .nl file export.
See also:
- MPS file format
- Writing .nl files
- nl (format) (Wikipedia)