Exemple #1
0
def test_more_inverse():
    a = Matrix([[8, -5, 9, 2], [7, 5, 6, 1], [-6, 0, 9, 6], [-3, 0, -9, -4]])
    a_exp = Matrix([
        [-0.15385, -0.15385, -0.28205, -0.53846],
        [-0.07692, 0.12308, 0.02564, 0.03077],
        [0.35897, 0.35897, 0.43590, 0.92308],
        [-0.69231, -0.69231, -0.76923, -1.92308],
    ])
    assert a.inverse() == a_exp

    b = Matrix([[9, 3, 0, 9], [-5, -2, -6, -3], [-4, 9, 6, 4], [-7, 6, 6, 2]])
    b_exp = Matrix([
        [-0.04074, -0.07778, 0.14444, -0.22222],
        [-0.07778, 0.03333, 0.36667, -0.33333],
        [-0.02901, -0.14630, -0.10926, 0.12963],
        [0.17778, 0.06667, -0.26667, 0.33333],
    ])
    assert b.inverse() == b_exp
Exemple #2
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def test_inverse():
    a = Matrix([[-5, 2, 6, -8], [1, -5, 1, 8], [7, 7, -6, -7], [1, -3, 7, 4]])
    b = a.inverse()
    assert a.determinant() == 532
    assert a.cofactor(2, 3) == -160
    assert b[3][2] == -160 / 532
    assert a.cofactor(3, 2) == 105
    assert b[2][3] == 105 / 532
    b_exp = Matrix([
        [0.21805, 0.45113, 0.24060, -0.04511],
        [-0.80827, -1.45677, -0.44361, 0.52068],
        [-0.07895, -0.22368, -0.05263, 0.19737],
        [-0.52256, -0.81391, -0.30075, 0.30639],
    ])
    assert b_exp == b
Exemple #3
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def test_inverse_mult():
    a = Matrix([[3, -9, 7, 3], [3, -8, 2, -9], [-4, 4, 4, 1], [-6, 5, -1, 1]])
    b = Matrix([[8, 2, 2, 2], [3, -1, 7, 0], [7, 0, 5, 4], [6, -2, 0, 5]])
    c = a * b
    assert c * b.inverse() == a