change seed in cp solver c++?

[515orestis]

i am using cp solver to solve a routing problem i am trying unsuccessfully to introduce randomness
on my problem( using reseed) is there a flag or any other specific configuration that i need to do?

using or tools 7.1
and best_insertions

if you need more info i will be more than happy to help

[Mizux]

in C++ (on master branch!) we have:

or-tools/ortools/constraint_solver/constraint_solver.cc

Lines 89 to 92 in 2fc5d0c

	DEFINE_int64(cp_random_seed, 12345,
	"Random seed used in several (but not all) random number "
	"generators used by the CP solver. Use -1 to auto-generate an"
	"undeterministic random seed.");

or-tools/ortools/constraint_solver/constraint_solver.h

Lines 92 to 94 in 2fc5d0c

	#if !defined(SWIG)
	DECLARE_int64(cp_random_seed);
	#endif // !defined(SWIG)

which won't be binded in Python, Java or .Net

[vgala]

How can i achieve the same in Python ?

[PeterSR]

@Mizux - Is this still not possible to control via Python?

And does it mean that if we don't change it, it will be deterministic?

[lperron]

Just parse the header file:

or-tools/ortools/constraint_solver/constraint_solver.h

Line 2929 in 5425ded

/// Reseed the solver random generator.

Which is correctly wrapped in python.