""" Additional tests for the mjo.cone.cone module. These are extra properties that we'd like to check, but which are overkill for inclusion into Sage. """ # Sage doesn't load ~/.sage/init.sage during testing (sage -t), so we # have to explicitly mangle our sitedir here so that "mjo.cone" # resolves. from os.path import abspath from site import addsitedir addsitedir(abspath('../../')) from sage.all import * # The double-import is needed to get the underscore methods. from mjo.cone.cone import * from mjo.cone.cone import _restrict_to_space # # Tests for _restrict_to_space. # def _look_isomorphic(K1, K2): r""" Test whether or not ``K1`` and ``K2`` look linearly isomorphic. This is a hack to get around the fact that it's difficult to tell when two cones are linearly isomorphic. Instead, we check a list of properties that should be preserved under linear isomorphism. OUTPUT: ``True`` if ``K1`` and ``K2`` look isomorphic, or ``False`` if we can prove that they are not isomorphic. EXAMPLES: Any proper cone with three generators in `\mathbb{R}^{3}` is isomorphic to the nonnegative orthant:: sage: K1 = Cone([(1,0,0), (0,1,0), (0,0,1)]) sage: K2 = Cone([(1,2,3), (3, 18, 4), (66, 51, 0)]) sage: _look_isomorphic(K1, K2) True Negating a cone gives you an isomorphic cone:: sage: K = Cone([(0,2,-5), (-6, 2, 4), (0, 51, 0)]) sage: _look_isomorphic(K, -K) True TESTS: Any cone is isomorphic to itself:: sage: K = random_cone(max_ambient_dim = 8) sage: _look_isomorphic(K, K) True After applying an invertible matrix to the rows of a cone, the result should is isomorphic to the cone we started with:: sage: K1 = random_cone(max_ambient_dim = 8) sage: A = random_matrix(QQ, K1.lattice_dim(), algorithm='unimodular') sage: K2 = Cone( [ A*r for r in K1.rays() ], lattice=K1.lattice()) sage: _look_isomorphic(K1, K2) True """ if K1.lattice_dim() != K2.lattice_dim(): return False if K1.nrays() != K2.nrays(): return False if K1.dim() != K2.dim(): return False if K1.lineality() != K2.lineality(): return False if K1.is_solid() != K2.is_solid(): return False if K1.is_strictly_convex() != K2.is_strictly_convex(): return False if len(K1.lyapunov_like_basis()) != len(K2.lyapunov_like_basis()): return False C_of_K1 = K1.discrete_complementarity_set() C_of_K2 = K2.discrete_complementarity_set() if len(C_of_K1) != len(C_of_K2): return False if len(K1.facets()) != len(K2.facets()): return False return True """ Apply _restrict_to_space according to our paper (to obtain our main result). Test all four parameter combinations:: sage: set_random_seed() sage: K = random_cone(max_ambient_dim = 8, ....: strictly_convex=False, ....: solid=False) sage: K_S = _restrict_to_space(K, K.span()) sage: K_SP = _restrict_to_space(K_S.dual(), K_S.dual().span()).dual() sage: K_SP.is_proper() True sage: K_SP = _restrict_to_space(K_S, K_S.dual().span()) sage: K_SP.is_proper() True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim = 8, ....: strictly_convex=True, ....: solid=False) sage: K_S = _restrict_to_space(K, K.span()) sage: K_SP = _restrict_to_space(K_S.dual(), K_S.dual().span()).dual() sage: K_SP.is_proper() True sage: K_SP = _restrict_to_space(K_S, K_S.dual().span()) sage: K_SP.is_proper() True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim = 8, ....: strictly_convex=False, ....: solid=True) sage: K_S = _restrict_to_space(K, K.span()) sage: K_SP = _restrict_to_space(K_S.dual(), K_S.dual().span()).dual() sage: K_SP.is_proper() True sage: K_SP = _restrict_to_space(K_S, K_S.dual().span()) sage: K_SP.is_proper() True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim = 8, ....: strictly_convex=True, ....: solid=True) sage: K_S = _restrict_to_space(K, K.span()) sage: K_SP = _restrict_to_space(K_S.dual(), K_S.dual().span()).dual() sage: K_SP.is_proper() True sage: K_SP = _restrict_to_space(K_S, K_S.dual().span()) sage: K_SP.is_proper() True Test the proposition in our paper concerning the duals and restrictions. Generate a random cone, then create a subcone of it. The operation of dual-taking should then commute with rho. Test all parameter combinations:: sage: set_random_seed() sage: J = random_cone(max_ambient_dim = 8, ....: solid=False, ....: strictly_convex=False) sage: K = Cone(random_sublist(J.rays(), 0.5), lattice=J.lattice()) sage: K_W_star = _restrict_to_space(K, J.span()).dual() sage: K_star_W = _restrict_to_space(K.dual(), J.span()) sage: _look_isomorphic(K_W_star, K_star_W) True :: sage: set_random_seed() sage: J = random_cone(max_ambient_dim = 8, ....: solid=True, ....: strictly_convex=False) sage: K = Cone(random_sublist(J.rays(), 0.5), lattice=J.lattice()) sage: K_W_star = _restrict_to_space(K, J.span()).dual() sage: K_star_W = _restrict_to_space(K.dual(), J.span()) sage: _look_isomorphic(K_W_star, K_star_W) True :: sage: set_random_seed() sage: J = random_cone(max_ambient_dim = 8, ....: solid=False, ....: strictly_convex=True) sage: K = Cone(random_sublist(J.rays(), 0.5), lattice=J.lattice()) sage: K_W_star = _restrict_to_space(K, J.span()).dual() sage: K_star_W = _restrict_to_space(K.dual(), J.span()) sage: _look_isomorphic(K_W_star, K_star_W) True :: sage: set_random_seed() sage: J = random_cone(max_ambient_dim = 8, ....: solid=True, ....: strictly_convex=True) sage: K = Cone(random_sublist(J.rays(), 0.5), lattice=J.lattice()) sage: K_W_star = _restrict_to_space(K, J.span()).dual() sage: K_star_W = _restrict_to_space(K.dual(), J.span()) sage: _look_isomorphic(K_W_star, K_star_W) True """ # # Lyapunov rank tests # """ The Lyapunov rank is invariant under a linear isomorphism. Check all combinations of parameters:: sage: K1 = random_cone(max_ambient_dim=8, ....: strictly_convex=True, ....: solid=True) sage: A = random_matrix(QQ, K1.lattice_dim(), algorithm='unimodular') sage: K2 = Cone( [ A*r for r in K1.rays() ], lattice=K1.lattice()) sage: lyapunov_rank(K1) == lyapunov_rank(K2) True :: sage: K1 = random_cone(max_ambient_dim=8, ....: strictly_convex=True, ....: solid=False) sage: A = random_matrix(QQ, K1.lattice_dim(), algorithm='unimodular') sage: K2 = Cone( [ A*r for r in K1.rays() ], lattice=K1.lattice()) sage: lyapunov_rank(K1) == lyapunov_rank(K2) True :: sage: K1 = random_cone(max_ambient_dim=8, ....: strictly_convex=False, ....: solid=True) sage: A = random_matrix(QQ, K1.lattice_dim(), algorithm='unimodular') sage: K2 = Cone( [ A*r for r in K1.rays() ], lattice=K1.lattice()) sage: lyapunov_rank(K1) == lyapunov_rank(K2) True :: sage: K1 = random_cone(max_ambient_dim=8, ....: strictly_convex=False, ....: solid=False) sage: A = random_matrix(QQ, K1.lattice_dim(), algorithm='unimodular') sage: K2 = Cone( [ A*r for r in K1.rays() ], lattice=K1.lattice()) sage: lyapunov_rank(K1) == lyapunov_rank(K2) True The Lyapunov rank of a dual cone should be the same as the original cone. Check all combinations of parameters:: sage: set_random_seed() sage: K = random_cone(max_ambient_dim=8, ....: strictly_convex=False, ....: solid=False) sage: lyapunov_rank(K) == lyapunov_rank(K.dual()) True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim=8, ....: strictly_convex=False, ....: solid=True) sage: lyapunov_rank(K) == lyapunov_rank(K.dual()) True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim=8, ....: strictly_convex=True, ....: solid=False) sage: lyapunov_rank(K) == lyapunov_rank(K.dual()) True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim=8, ....: strictly_convex=True, ....: solid=True) sage: lyapunov_rank(K) == lyapunov_rank(K.dual()) True The Lyapunov rank of a cone ``K`` is the dimension of ``K.lyapunov_like_basis()``. Check all combinations of parameters:: sage: set_random_seed() sage: K = random_cone(max_ambient_dim=8, ....: strictly_convex=True, ....: solid=True) sage: lyapunov_rank(K) == len(K.lyapunov_like_basis()) True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim=8, ....: strictly_convex=True, ....: solid=False) sage: lyapunov_rank(K) == len(K.lyapunov_like_basis()) True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim=8, ....: strictly_convex=False, ....: solid=True) sage: lyapunov_rank(K) == len(K.lyapunov_like_basis()) True :: sage: set_random_seed() sage: K = random_cone(max_ambient_dim=8, ....: strictly_convex=False, ....: solid=False) sage: lyapunov_rank(K) == len(K.lyapunov_like_basis()) True """