Python rsolve_ratio Examples

Example #1

File: test_recurr.py Project: fagan2888/diofant

def test_ratio():
    assert rsolve_ratio([
        -2 * n**3 + n**2 + 2 * n - 1, 2 * n**3 + n**2 - 6 * n,
        -2 * n**3 - 11 * n**2 - 18 * n - 9, 2 * n**3 + 13 * n**2 + 22 * n + 8
    ], 0, n) == (C2 * (2 * n - 3) / (n**2 - 1) / 2, [C2])
    assert rsolve_ratio([1, 1], sqrt(n), n) is None
    assert rsolve_ratio([-n**3, n + 1], n, n) is None

Example #2

File: test_recurr.py Project: skirpichev/diofant

def test_rsolve_ratio():
    solution = rsolve_ratio([-2*n**3 + n**2 + 2*n - 1, 2*n**3 + n**2 - 6*n,
                             -2*n**3 - 11*n**2 - 18*n - 9, 2*n**3 + 13*n**2 + 22*n + 8], 0, n)

    assert solution in [
        C1*((-2*n + 3)/(n**2 - 1))/3,
        (C1*(-3 + 2*n)/(-1 + n**2))/2,
        (C1*( 3 - 2*n)/( 1 - n**2))/2,
        (C2*(-3 + 2*n)/(-1 + n**2))/2,
        (C2*( 3 - 2*n)/( 1 - n**2))/2,
    ]

    assert rsolve_ratio([1, 1], sqrt(n), n) is None
    assert rsolve_ratio([-n**3, n + 1], n, n) is None

Example #3

File: test_recurr.py Project: goretkin/diofant

def test_rsolve_ratio():
    solution = rsolve_ratio([
        -2 * n**3 + n**2 + 2 * n - 1, 2 * n**3 + n**2 - 6 * n,
        -2 * n**3 - 11 * n**2 - 18 * n - 9, 2 * n**3 + 13 * n**2 + 22 * n + 8
    ], 0, n)

    assert solution in [
        C1 * ((-2 * n + 3) / (n**2 - 1)) / 3,
        (Rational(1, 2)) * (C1 * (-3 + 2 * n) / (-1 + n**2)),
        (Rational(1, 2)) * (C1 * (3 - 2 * n) / (1 - n**2)),
        (Rational(1, 2)) * (C2 * (-3 + 2 * n) / (-1 + n**2)),
        (Rational(1, 2)) * (C2 * (3 - 2 * n) / (1 - n**2)),
    ]

    assert rsolve_ratio([1, 1], sqrt(n), n) is None