phivenv/Lib/site-packages/sympy/matrices/expressions/tests/test_factorizations.py

from sympy.matrices.expressions.factorizations import lu, LofCholesky, qr, svd
from sympy.assumptions.ask import (Q, ask)
from sympy.core.symbol import Symbol
from sympy.matrices.expressions.matexpr import MatrixSymbol

n = Symbol('n')
X = MatrixSymbol('X', n, n)

def test_LU():
    L, U = lu(X)
    assert L.shape == U.shape == X.shape
    assert ask(Q.lower_triangular(L))
    assert ask(Q.upper_triangular(U))

def test_Cholesky():
    LofCholesky(X)

def test_QR():
    Q_, R = qr(X)
    assert Q_.shape == R.shape == X.shape
    assert ask(Q.orthogonal(Q_))
    assert ask(Q.upper_triangular(R))

def test_svd():
    U, S, V = svd(X)
    assert U.shape == S.shape == V.shape == X.shape
    assert ask(Q.orthogonal(U))
    assert ask(Q.orthogonal(V))
    assert ask(Q.diagonal(S))