""" Tests for the sympy.polys.matrices.eigen module """ from sympy.core.singleton import S from sympy.functions.elementary.miscellaneous import sqrt from sympy.matrices.dense import Matrix from sympy.polys.agca.extensions import FiniteExtension from sympy.polys.domains import QQ from sympy.polys.polytools import Poly from sympy.polys.rootoftools import CRootOf from sympy.polys.matrices.domainmatrix import DomainMatrix from sympy.polys.matrices.eigen import dom_eigenvects, dom_eigenvects_to_sympy def test_dom_eigenvects_rational(): # Rational eigenvalues A = DomainMatrix([[QQ(1), QQ(2)], [QQ(1), QQ(2)]], (2, 2), QQ) rational_eigenvects = [ (QQ, QQ(3), 1, DomainMatrix([[QQ(1), QQ(1)]], (1, 2), QQ)), (QQ, QQ(0), 1, DomainMatrix([[QQ(-2), QQ(1)]], (1, 2), QQ)), ] assert dom_eigenvects(A) == (rational_eigenvects, []) # Test converting to Expr: sympy_eigenvects = [ (S(3), 1, [Matrix([1, 1])]), (S(0), 1, [Matrix([-2, 1])]), ] assert dom_eigenvects_to_sympy(rational_eigenvects, [], Matrix) == sympy_eigenvects def test_dom_eigenvects_algebraic(): # Algebraic eigenvalues A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) Avects = dom_eigenvects(A) # Extract the dummy to build the expected result: lamda = Avects[1][0][1].gens[0] irreducible = Poly(lamda**2 - 5*lamda - 2, lamda, domain=QQ) K = FiniteExtension(irreducible) KK = K.from_sympy algebraic_eigenvects = [ (K, irreducible, 1, DomainMatrix([[KK((lamda-4)/3), KK(1)]], (1, 2), K)), ] assert Avects == ([], algebraic_eigenvects) # Test converting to Expr: sympy_eigenvects = [ (S(5)/2 - sqrt(33)/2, 1, [Matrix([[-sqrt(33)/6 - S(1)/2], [1]])]), (S(5)/2 + sqrt(33)/2, 1, [Matrix([[-S(1)/2 + sqrt(33)/6], [1]])]), ] assert dom_eigenvects_to_sympy([], algebraic_eigenvects, Matrix) == sympy_eigenvects def test_dom_eigenvects_rootof(): # Algebraic eigenvalues A = DomainMatrix([ [0, 0, 0, 0, -1], [1, 0, 0, 0, 1], [0, 1, 0, 0, 0], [0, 0, 1, 0, 0], [0, 0, 0, 1, 0]], (5, 5), QQ) Avects = dom_eigenvects(A) # Extract the dummy to build the expected result: lamda = Avects[1][0][1].gens[0] irreducible = Poly(lamda**5 - lamda + 1, lamda, domain=QQ) K = FiniteExtension(irreducible) KK = K.from_sympy algebraic_eigenvects = [ (K, irreducible, 1, DomainMatrix([ [KK(lamda**4-1), KK(lamda**3), KK(lamda**2), KK(lamda), KK(1)] ], (1, 5), K)), ] assert Avects == ([], algebraic_eigenvects) # Test converting to Expr (slow): l0, l1, l2, l3, l4 = [CRootOf(lamda**5 - lamda + 1, i) for i in range(5)] sympy_eigenvects = [ (l0, 1, [Matrix([-1 + l0**4, l0**3, l0**2, l0, 1])]), (l1, 1, [Matrix([-1 + l1**4, l1**3, l1**2, l1, 1])]), (l2, 1, [Matrix([-1 + l2**4, l2**3, l2**2, l2, 1])]), (l3, 1, [Matrix([-1 + l3**4, l3**3, l3**2, l3, 1])]), (l4, 1, [Matrix([-1 + l4**4, l4**3, l4**2, l4, 1])]), ] assert dom_eigenvects_to_sympy([], algebraic_eigenvects, Matrix) == sympy_eigenvects