test_miscellaneous.py 文件源码

def test_root():
    from sympy.abc import x, y, z
    n = Symbol('n', integer=True)

    assert root(2, 2) == sqrt(2)
    assert root(2, 1) == 2
    assert root(2, 3) == 2**Rational(1, 3)
    assert root(2, 3) == cbrt(2)
    assert root(2, -5) == 2**Rational(4, 5)/2

    assert root(-2, 1) == -2

    assert root(-2, 2) == sqrt(2)*I
    assert root(-2, 1) == -2

    assert root(x, 2) == sqrt(x)
    assert root(x, 1) == x
    assert root(x, 3) == x**Rational(1, 3)
    assert root(x, 3) == cbrt(x)
    assert root(x, -5) == x**Rational(-1, 5)

    assert root(x, n) == x**(1/n)
    assert root(x, -n) == x**(-1/n)