ai-content-maker/.venv/Lib/site-packages/sympy/matrices/tests/test_decompositions.py

475 lines
14 KiB
Python

from sympy.core.function import expand_mul
from sympy.core.numbers import I, Rational
from sympy.core.singleton import S
from sympy.core.symbol import Symbol
from sympy.functions.elementary.miscellaneous import sqrt
from sympy.functions.elementary.complexes import Abs
from sympy.simplify.simplify import simplify
from sympy.matrices.matrices import NonSquareMatrixError
from sympy.matrices import Matrix, zeros, eye, SparseMatrix
from sympy.abc import x, y, z
from sympy.testing.pytest import raises, slow
from sympy.testing.matrices import allclose
def test_LUdecomp():
testmat = Matrix([[0, 2, 5, 3],
[3, 3, 7, 4],
[8, 4, 0, 2],
[-2, 6, 3, 4]])
L, U, p = testmat.LUdecomposition()
assert L.is_lower
assert U.is_upper
assert (L*U).permute_rows(p, 'backward') - testmat == zeros(4)
testmat = Matrix([[6, -2, 7, 4],
[0, 3, 6, 7],
[1, -2, 7, 4],
[-9, 2, 6, 3]])
L, U, p = testmat.LUdecomposition()
assert L.is_lower
assert U.is_upper
assert (L*U).permute_rows(p, 'backward') - testmat == zeros(4)
# non-square
testmat = Matrix([[1, 2, 3],
[4, 5, 6],
[7, 8, 9],
[10, 11, 12]])
L, U, p = testmat.LUdecomposition(rankcheck=False)
assert L.is_lower
assert U.is_upper
assert (L*U).permute_rows(p, 'backward') - testmat == zeros(4, 3)
# square and singular
testmat = Matrix([[1, 2, 3],
[2, 4, 6],
[4, 5, 6]])
L, U, p = testmat.LUdecomposition(rankcheck=False)
assert L.is_lower
assert U.is_upper
assert (L*U).permute_rows(p, 'backward') - testmat == zeros(3)
M = Matrix(((1, x, 1), (2, y, 0), (y, 0, z)))
L, U, p = M.LUdecomposition()
assert L.is_lower
assert U.is_upper
assert (L*U).permute_rows(p, 'backward') - M == zeros(3)
mL = Matrix((
(1, 0, 0),
(2, 3, 0),
))
assert mL.is_lower is True
assert mL.is_upper is False
mU = Matrix((
(1, 2, 3),
(0, 4, 5),
))
assert mU.is_lower is False
assert mU.is_upper is True
# test FF LUdecomp
M = Matrix([[1, 3, 3],
[3, 2, 6],
[3, 2, 2]])
P, L, Dee, U = M.LUdecompositionFF()
assert P*M == L*Dee.inv()*U
M = Matrix([[1, 2, 3, 4],
[3, -1, 2, 3],
[3, 1, 3, -2],
[6, -1, 0, 2]])
P, L, Dee, U = M.LUdecompositionFF()
assert P*M == L*Dee.inv()*U
M = Matrix([[0, 0, 1],
[2, 3, 0],
[3, 1, 4]])
P, L, Dee, U = M.LUdecompositionFF()
assert P*M == L*Dee.inv()*U
# issue 15794
M = Matrix(
[[1, 2, 3],
[4, 5, 6],
[7, 8, 9]]
)
raises(ValueError, lambda : M.LUdecomposition_Simple(rankcheck=True))
def test_singular_value_decompositionD():
A = Matrix([[1, 2], [2, 1]])
U, S, V = A.singular_value_decomposition()
assert U * S * V.T == A
assert U.T * U == eye(U.cols)
assert V.T * V == eye(V.cols)
B = Matrix([[1, 2]])
U, S, V = B.singular_value_decomposition()
assert U * S * V.T == B
assert U.T * U == eye(U.cols)
assert V.T * V == eye(V.cols)
C = Matrix([
[1, 0, 0, 0, 2],
[0, 0, 3, 0, 0],
[0, 0, 0, 0, 0],
[0, 2, 0, 0, 0],
])
U, S, V = C.singular_value_decomposition()
assert U * S * V.T == C
assert U.T * U == eye(U.cols)
assert V.T * V == eye(V.cols)
D = Matrix([[Rational(1, 3), sqrt(2)], [0, Rational(1, 4)]])
U, S, V = D.singular_value_decomposition()
assert simplify(U.T * U) == eye(U.cols)
assert simplify(V.T * V) == eye(V.cols)
assert simplify(U * S * V.T) == D
def test_QR():
A = Matrix([[1, 2], [2, 3]])
Q, S = A.QRdecomposition()
R = Rational
assert Q == Matrix([
[ 5**R(-1, 2), (R(2)/5)*(R(1)/5)**R(-1, 2)],
[2*5**R(-1, 2), (-R(1)/5)*(R(1)/5)**R(-1, 2)]])
assert S == Matrix([[5**R(1, 2), 8*5**R(-1, 2)], [0, (R(1)/5)**R(1, 2)]])
assert Q*S == A
assert Q.T * Q == eye(2)
A = Matrix([[1, 1, 1], [1, 1, 3], [2, 3, 4]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[12, 0, -51], [6, 0, 167], [-4, 0, 24]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
x = Symbol('x')
A = Matrix([x])
Q, R = A.QRdecomposition()
assert Q == Matrix([x / Abs(x)])
assert R == Matrix([Abs(x)])
A = Matrix([[x, 0], [0, x]])
Q, R = A.QRdecomposition()
assert Q == x / Abs(x) * Matrix([[1, 0], [0, 1]])
assert R == Abs(x) * Matrix([[1, 0], [0, 1]])
def test_QR_non_square():
# Narrow (cols < rows) matrices
A = Matrix([[9, 0, 26], [12, 0, -7], [0, 4, 4], [0, -3, -3]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[1, -1, 4], [1, 4, -2], [1, 4, 2], [1, -1, 0]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix(2, 1, [1, 2])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
# Wide (cols > rows) matrices
A = Matrix([[1, 2, 3], [4, 5, 6]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[1, 2, 3, 4], [1, 4, 9, 16], [1, 8, 27, 64]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix(1, 2, [1, 2])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
def test_QR_trivial():
# Rank deficient matrices
A = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[1, 1, 1], [2, 2, 2], [3, 3, 3], [4, 4, 4]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[1, 1, 1], [2, 2, 2], [3, 3, 3], [4, 4, 4]]).T
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
# Zero rank matrices
A = Matrix([[0, 0, 0]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[0, 0, 0]]).T
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[0, 0, 0], [0, 0, 0]])
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[0, 0, 0], [0, 0, 0]]).T
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
# Rank deficient matrices with zero norm from beginning columns
A = Matrix([[0, 0, 0], [1, 2, 3]]).T
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[0, 0, 0, 0], [1, 2, 3, 4], [0, 0, 0, 0]]).T
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[0, 0, 0, 0], [1, 2, 3, 4], [0, 0, 0, 0], [2, 4, 6, 8]]).T
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
A = Matrix([[0, 0, 0], [0, 0, 0], [0, 0, 0], [1, 2, 3]]).T
Q, R = A.QRdecomposition()
assert Q.T * Q == eye(Q.cols)
assert R.is_upper
assert A == Q*R
def test_QR_float():
A = Matrix([[1, 1], [1, 1.01]])
Q, R = A.QRdecomposition()
assert allclose(Q * R, A)
assert allclose(Q * Q.T, Matrix.eye(2))
assert allclose(Q.T * Q, Matrix.eye(2))
A = Matrix([[1, 1], [1, 1.001]])
Q, R = A.QRdecomposition()
assert allclose(Q * R, A)
assert allclose(Q * Q.T, Matrix.eye(2))
assert allclose(Q.T * Q, Matrix.eye(2))
def test_LUdecomposition_Simple_iszerofunc():
# Test if callable passed to matrices.LUdecomposition_Simple() as iszerofunc keyword argument is used inside
# matrices.LUdecomposition_Simple()
magic_string = "I got passed in!"
def goofyiszero(value):
raise ValueError(magic_string)
try:
lu, p = Matrix([[1, 0], [0, 1]]).LUdecomposition_Simple(iszerofunc=goofyiszero)
except ValueError as err:
assert magic_string == err.args[0]
return
assert False
def test_LUdecomposition_iszerofunc():
# Test if callable passed to matrices.LUdecomposition() as iszerofunc keyword argument is used inside
# matrices.LUdecomposition_Simple()
magic_string = "I got passed in!"
def goofyiszero(value):
raise ValueError(magic_string)
try:
l, u, p = Matrix([[1, 0], [0, 1]]).LUdecomposition(iszerofunc=goofyiszero)
except ValueError as err:
assert magic_string == err.args[0]
return
assert False
def test_LDLdecomposition():
raises(NonSquareMatrixError, lambda: Matrix((1, 2)).LDLdecomposition())
raises(ValueError, lambda: Matrix(((1, 2), (3, 4))).LDLdecomposition())
raises(ValueError, lambda: Matrix(((5 + I, 0), (0, 1))).LDLdecomposition())
raises(ValueError, lambda: Matrix(((1, 5), (5, 1))).LDLdecomposition())
raises(ValueError, lambda: Matrix(((1, 2), (3, 4))).LDLdecomposition(hermitian=False))
A = Matrix(((1, 5), (5, 1)))
L, D = A.LDLdecomposition(hermitian=False)
assert L * D * L.T == A
A = Matrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11)))
L, D = A.LDLdecomposition()
assert L * D * L.T == A
assert L.is_lower
assert L == Matrix([[1, 0, 0], [ Rational(3, 5), 1, 0], [Rational(-1, 5), Rational(1, 3), 1]])
assert D.is_diagonal()
assert D == Matrix([[25, 0, 0], [0, 9, 0], [0, 0, 9]])
A = Matrix(((4, -2*I, 2 + 2*I), (2*I, 2, -1 + I), (2 - 2*I, -1 - I, 11)))
L, D = A.LDLdecomposition()
assert expand_mul(L * D * L.H) == A
assert L.expand() == Matrix([[1, 0, 0], [I/2, 1, 0], [S.Half - I/2, 0, 1]])
assert D.expand() == Matrix(((4, 0, 0), (0, 1, 0), (0, 0, 9)))
raises(NonSquareMatrixError, lambda: SparseMatrix((1, 2)).LDLdecomposition())
raises(ValueError, lambda: SparseMatrix(((1, 2), (3, 4))).LDLdecomposition())
raises(ValueError, lambda: SparseMatrix(((5 + I, 0), (0, 1))).LDLdecomposition())
raises(ValueError, lambda: SparseMatrix(((1, 5), (5, 1))).LDLdecomposition())
raises(ValueError, lambda: SparseMatrix(((1, 2), (3, 4))).LDLdecomposition(hermitian=False))
A = SparseMatrix(((1, 5), (5, 1)))
L, D = A.LDLdecomposition(hermitian=False)
assert L * D * L.T == A
A = SparseMatrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11)))
L, D = A.LDLdecomposition()
assert L * D * L.T == A
assert L.is_lower
assert L == Matrix([[1, 0, 0], [ Rational(3, 5), 1, 0], [Rational(-1, 5), Rational(1, 3), 1]])
assert D.is_diagonal()
assert D == Matrix([[25, 0, 0], [0, 9, 0], [0, 0, 9]])
A = SparseMatrix(((4, -2*I, 2 + 2*I), (2*I, 2, -1 + I), (2 - 2*I, -1 - I, 11)))
L, D = A.LDLdecomposition()
assert expand_mul(L * D * L.H) == A
assert L == Matrix(((1, 0, 0), (I/2, 1, 0), (S.Half - I/2, 0, 1)))
assert D == Matrix(((4, 0, 0), (0, 1, 0), (0, 0, 9)))
def test_pinv_succeeds_with_rank_decomposition_method():
# Test rank decomposition method of pseudoinverse succeeding
As = [Matrix([
[61, 89, 55, 20, 71, 0],
[62, 96, 85, 85, 16, 0],
[69, 56, 17, 4, 54, 0],
[10, 54, 91, 41, 71, 0],
[ 7, 30, 10, 48, 90, 0],
[0,0,0,0,0,0]])]
for A in As:
A_pinv = A.pinv(method="RD")
AAp = A * A_pinv
ApA = A_pinv * A
assert simplify(AAp * A) == A
assert simplify(ApA * A_pinv) == A_pinv
assert AAp.H == AAp
assert ApA.H == ApA
def test_rank_decomposition():
a = Matrix(0, 0, [])
c, f = a.rank_decomposition()
assert f.is_echelon
assert c.cols == f.rows == a.rank()
assert c * f == a
a = Matrix(1, 1, [5])
c, f = a.rank_decomposition()
assert f.is_echelon
assert c.cols == f.rows == a.rank()
assert c * f == a
a = Matrix(3, 3, [1, 2, 3, 1, 2, 3, 1, 2, 3])
c, f = a.rank_decomposition()
assert f.is_echelon
assert c.cols == f.rows == a.rank()
assert c * f == a
a = Matrix([
[0, 0, 1, 2, 2, -5, 3],
[-1, 5, 2, 2, 1, -7, 5],
[0, 0, -2, -3, -3, 8, -5],
[-1, 5, 0, -1, -2, 1, 0]])
c, f = a.rank_decomposition()
assert f.is_echelon
assert c.cols == f.rows == a.rank()
assert c * f == a
@slow
def test_upper_hessenberg_decomposition():
A = Matrix([
[1, 0, sqrt(3)],
[sqrt(2), Rational(1, 2), 2],
[1, Rational(1, 4), 3],
])
H, P = A.upper_hessenberg_decomposition()
assert simplify(P * P.H) == eye(P.cols)
assert simplify(P.H * P) == eye(P.cols)
assert H.is_upper_hessenberg
assert (simplify(P * H * P.H)) == A
B = Matrix([
[1, 2, 10],
[8, 2, 5],
[3, 12, 34],
])
H, P = B.upper_hessenberg_decomposition()
assert simplify(P * P.H) == eye(P.cols)
assert simplify(P.H * P) == eye(P.cols)
assert H.is_upper_hessenberg
assert simplify(P * H * P.H) == B
C = Matrix([
[1, sqrt(2), 2, 3],
[0, 5, 3, 4],
[1, 1, 4, sqrt(5)],
[0, 2, 2, 3]
])
H, P = C.upper_hessenberg_decomposition()
assert simplify(P * P.H) == eye(P.cols)
assert simplify(P.H * P) == eye(P.cols)
assert H.is_upper_hessenberg
assert simplify(P * H * P.H) == C
D = Matrix([
[1, 2, 3],
[-3, 5, 6],
[4, -8, 9],
])
H, P = D.upper_hessenberg_decomposition()
assert simplify(P * P.H) == eye(P.cols)
assert simplify(P.H * P) == eye(P.cols)
assert H.is_upper_hessenberg
assert simplify(P * H * P.H) == D
E = Matrix([
[1, 0, 0, 0],
[0, 1, 0, 0],
[1, 1, 0, 1],
[1, 1, 1, 0]
])
H, P = E.upper_hessenberg_decomposition()
assert simplify(P * P.H) == eye(P.cols)
assert simplify(P.H * P) == eye(P.cols)
assert H.is_upper_hessenberg
assert simplify(P * H * P.H) == E