Search Parameters

All three solvers in PyQBPP — EasySolver, ExhaustiveSolver, and ABS3Solver — accept search parameters through search(). Parameters are passed as keyword arguments. Values can be strings, integers, or floats — they are automatically converted to strings before being passed to the backend.

Passing Parameters

Pass keyword arguments directly to search():

sol = solver.search(time_limit=10, target_energy=0)

Values can be mixed — strings, integers, and floats:

sol = solver.search(time_limit=2.5, target_energy="0")

When you need to build parameters programmatically, create a dict and pass it with **:

params = {}
params["time_limit"] = 10
params["target_energy"] = 0
sol = solver.search(**params)

No special Params object is needed — keyword arguments are all that is required. Internally, PyQBPP converts each value to a string and passes the key-value pairs to the solver.

Common Parameters

The following parameters are shared by all three solvers:

Parameter	Type	Description
target_energy	int	Stop when a solution with energy ≤ this value is found.
enable_default_callback	int (0/1)	Print newly obtained best solutions to stderr. Default: 0.
topk_sols	int	Keep up to N top-k solutions during the search.
best_energy_sols	int (0/1)	Keep all solutions with the best energy. 0 = unlimited count.

EasySolver Parameters

Parameter	Type	Description	Default
time_limit	float	Time limit in seconds. 0 for no limit.	10.0
target_energy	int	Target energy.	(none)
enable_default_callback	int (0/1)	Print progress.	0
topk_sols	int	Top-k solutions to keep.	(disabled)
best_energy_sols	int	Best-energy solutions to keep.	(disabled)

Example:

solver = qbpp.EasySolver(f)
sol = solver.search(time_limit=5, target_energy=0)

ExhaustiveSolver Parameters

The ExhaustiveSolver does not have a time_limit parameter because it performs a complete search.

Parameter	Type	Description	Default
target_energy	int	Target energy (for early termination).	(none)
verbose	int (0/1)	Display search progress percentage.	0
enable_default_callback	int (0/1)	Print progress.	0
topk_sols	int	Top-k solutions to keep.	(disabled)
best_energy_sols	int (0/1)	Keep all optimal solutions.	(disabled)
all_sols	int (0/1)	Keep all feasible solutions.	(disabled)

Example:

solver = qbpp.ExhaustiveSolver(f)
sol = solver.search(target_energy=0)

Multiple solutions can be collected by combining parameters:

sol = solver.search(best_energy_sols=0, target_energy=0)
for s in sol.sols:
    print(s.energy)

ABS3Solver Parameters

Parameter	Type	Description	Default
time_limit	float	Time limit in seconds.	10.0
target_energy	int	Target energy.	(none)
enable_default_callback	int (0/1)	Print progress.	0
topk_sols	int	Top-k solutions to keep.	(disabled)
best_energy_sols	int (0/1)	Keep all optimal solutions.	(disabled)
cpu_enable	int (0/1)	Enable/disable CPU solver.	1
cpu_thread_count	int	Number of CPU threads.	(auto)
block_count	int	Number of GPU blocks.	(auto)
thread_count	int	Number of GPU threads per block.	(auto)

Example:

solver = qbpp.ABS3Solver(f)
sol = solver.search(time_limit=10, target_energy=0)

Error Handling

Unknown parameter keys will cause a runtime error.