Solver Backends

ILPDecoder uses a direct HiGHS backend by default. Optional backends are available for direct Gurobi (licensed) and for Pyomo-based solvers.

Backend Matrix

Solver	Backend	Install	Notes
HiGHS	Direct	pip install ilpdecoder	Default backend via highspy.
HiGHS	Pyomo	pip install ilpdecoder[pyomo] + HiGHS binary	Optional Pyomo path.
Gurobi	Direct	pip install ilpdecoder[gurobi]	Requires a valid license.
Gurobi	Pyomo	pip install ilpdecoder[pyomo] + gurobi	Uses Pyomo interface.
SCIP	Pyomo	pip install ilpdecoder[pyomo] + scip	Open source (binary required).
CBC	Pyomo	pip install ilpdecoder[pyomo] + cbc	Open source (binary required).
GLPK	Pyomo	pip install ilpdecoder[pyomo] + glpk	Open source (binary required).
CPLEX	Pyomo	pip install ilpdecoder[pyomo] + cplex	Commercial license.

Switching Solvers

from ilpdecoder import Decoder

# Create a decoder and switch backends later.
decoder = Decoder.from_parity_check_matrix(H)

# Use a Pyomo solver.
decoder.set_solver("scip", time_limit=30)

# Use the direct Gurobi backend (if installed).
decoder.set_solver("gurobi")

If a non-HiGHS solver is requested without Pyomo installed, ILPDecoder fails fast with a one-line install hint.

Solver Options

decoder.set_solver(
    "scip",
    direct=False,     # Use the Pyomo backend
    time_limit=30,    # Max solve time (seconds)
    gap=0.01,         # Relative ILP gap tolerance
    threads=4,        # Thread count (solver-dependent)
    verbose=True,     # Print solver output
)

Option	Description	Supported Solvers
time_limit	Max solving time (seconds)	All
gap	Relative ILP gap tolerance	All
threads	Thread count	HiGHS, Gurobi, CPLEX
verbose	Print solver output	All
direct	Use direct backend (default for HiGHS)	HiGHS, Gurobi

Availability Checks

get_available_solvers() lists solvers based on installed Python packages and (for Pyomo) solver discovery. The direct Gurobi backend can be imported without a valid license; a license error is raised when the solver is first used.