Python sympy.atanh函数代码示例

def test_issue_10847():
    assert manualintegrate(x**2 / (x**2 - c), x) == c*Piecewise((atan(x/sqrt(-c))/sqrt(-c), -c > 0), \
                                                                (-acoth(x/sqrt(c))/sqrt(c), And(-c < 0, x**2 > c)), \
                                                                (-atanh(x/sqrt(c))/sqrt(c), And(-c < 0, x**2 < c))) + x
    assert manualintegrate(sqrt(x - y) * log(z / x), x) == 4*y**2*Piecewise((atan(sqrt(x - y)/sqrt(y))/sqrt(y), y > 0), \
                                                                            (-acoth(sqrt(x - y)/sqrt(-y))/sqrt(-y), \
                                                                             And(x - y > -y, y < 0)), \
                                                                            (-atanh(sqrt(x - y)/sqrt(-y))/sqrt(-y), \
                                                                             And(x - y < -y, y < 0)))/3 \
                                                                             - 4*y*sqrt(x - y)/3 + 2*(x - y)**(S(3)/2)*log(z/x)/3 \
                                                                             + 4*(x - y)**(S(3)/2)/9

    assert manualintegrate(sqrt(x) * log(x), x) == 2*x**(S(3)/2)*log(x)/3 - 4*x**(S(3)/2)/9
    assert manualintegrate(sqrt(a*x + b) / x, x) == -2*b*Piecewise((-atan(sqrt(a*x + b)/sqrt(-b))/sqrt(-b), -b > 0), \
                                                               (acoth(sqrt(a*x + b)/sqrt(b))/sqrt(b), And(-b < 0, a*x + b > b)), \
                                                               (atanh(sqrt(a*x + b)/sqrt(b))/sqrt(b), And(-b < 0, a*x + b < b))) \
                                                               + 2*sqrt(a*x + b)

    assert expand(manualintegrate(sqrt(a*x + b) / (x + c), x)) == -2*a*c*Piecewise((atan(sqrt(a*x + b)/sqrt(a*c - b))/sqrt(a*c - b), \
        a*c - b > 0), (-acoth(sqrt(a*x + b)/sqrt(-a*c + b))/sqrt(-a*c + b), And(a*c - b < 0, a*x + b > -a*c + b)), \
        (-atanh(sqrt(a*x + b)/sqrt(-a*c + b))/sqrt(-a*c + b), And(a*c - b < 0, a*x + b < -a*c + b))) \
        + 2*b*Piecewise((atan(sqrt(a*x + b)/sqrt(a*c - b))/sqrt(a*c - b), a*c - b > 0), \
        (-acoth(sqrt(a*x + b)/sqrt(-a*c + b))/sqrt(-a*c + b), And(a*c - b < 0, a*x + b > -a*c + b)), \
        (-atanh(sqrt(a*x + b)/sqrt(-a*c + b))/sqrt(-a*c + b), And(a*c - b < 0, a*x + b < -a*c + b))) + 2*sqrt(a*x + b)

    assert manualintegrate((4*x**4 + 4*x**3 + 16*x**2 + 12*x + 8) \
                           / (x**6 + 2*x**5 + 3*x**4 + 4*x**3 + 3*x**2 + 2*x + 1), x) == \
                           2*x/(x**2 + 1) + 3*atan(x) - 1/(x**2 + 1) - 3/(x + 1)
    assert manualintegrate(sqrt(2*x + 3) / (x + 1), x) == 2*sqrt(2*x + 3) - log(sqrt(2*x + 3) + 1) + log(sqrt(2*x + 3) - 1)
    assert manualintegrate(sqrt(2*x + 3) / 2 * x, x) == (2*x + 3)**(S(5)/2)/20 - (2*x + 3)**(S(3)/2)/4
    assert manualintegrate(x**Rational(3,2) * log(x), x) == 2*x**Rational(5,2)*log(x)/5 - 4*x**Rational(5,2)/25
    assert manualintegrate(x**(-3) * log(x), x) == -log(x)/(2*x**2) - 1/(4*x**2)
    assert manualintegrate(log(y)/(y**2*(1 - 1/y)), y) == \
        log(y)*log(-1 + 1/y) - Integral(log(-1 + 1/y)/y, y)

def test_issue_1572_1364_1368():
    assert solve((sqrt(x**2 - 1) - 2)) in ([sqrt(5), -sqrt(5)],
                                           [-sqrt(5), sqrt(5)])
    assert set(solve((2**exp(y**2/x) + 2)/(x**2 + 15), y)) == set([
        -sqrt(x)*sqrt(-log(log(2)) + log(log(2) + I*pi)),
        sqrt(x)*sqrt(-log(log(2)) + log(log(2) + I*pi))])

    C1, C2 = symbols('C1 C2')
    f = Function('f')
    assert solve(C1 + C2/x**2 - exp(-f(x)), f(x)) == [log(x**2/(C1*x**2 + C2))]
    a = Symbol('a')
    E = S.Exp1
    assert solve(1 - log(a + 4*x**2), x) in (
        [-sqrt(-a + E)/2, sqrt(-a + E)/2],
        [sqrt(-a + E)/2, -sqrt(-a + E)/2]
    )
    assert solve(log(a**(-3) - x**2)/a, x) in (
        [-sqrt(-1 + a**(-3)), sqrt(-1 + a**(-3))],
        [sqrt(-1 + a**(-3)), -sqrt(-1 + a**(-3))],)
    assert solve(1 - log(a + 4*x**2), x) in (
        [-sqrt(-a + E)/2, sqrt(-a + E)/2],
        [sqrt(-a + E)/2, -sqrt(-a + E)/2],)
    assert set(solve((
        a**2 + 1) * (sin(a*x) + cos(a*x)), x)) == set([-pi/(4*a), 3*pi/(4*a)])
    assert solve(3 - (sinh(a*x) + cosh(a*x)), x) == [2*atanh(S.Half)/a]
    assert set(solve(3 - (sinh(a*x) + cosh(a*x)**2), x)) == \
        set([
            2*atanh(-1 + sqrt(2))/a,
            2*atanh(S(1)/2 + sqrt(5)/2)/a,
            2*atanh(-sqrt(2) - 1)/a,
            2*atanh(-sqrt(5)/2 + S(1)/2)/a
             ])
    assert solve(atan(x) - 1) == [tan(1)]

def test_rewrite_trigh():
    # if this import passes then the test below should also pass
    from sympy import sech
    assert solveset_real(sinh(x) + sech(x), x) == FiniteSet(
        2*atanh(-S.Half + sqrt(5)/2 - sqrt(-2*sqrt(5) + 2)/2),
        2*atanh(-S.Half + sqrt(5)/2 + sqrt(-2*sqrt(5) + 2)/2),
        2*atanh(-sqrt(5)/2 - S.Half + sqrt(2 + 2*sqrt(5))/2),
        2*atanh(-sqrt(2 + 2*sqrt(5))/2 - sqrt(5)/2 - S.Half))

def test_simplifications():
    x = Symbol("x")
    assert sinh(asinh(x)) == x
    assert sinh(acosh(x)) == sqrt(x - 1) * sqrt(x + 1)
    assert sinh(atanh(x)) == x / sqrt(1 - x ** 2)

    assert cosh(asinh(x)) == sqrt(1 + x ** 2)
    assert cosh(acosh(x)) == x
    assert cosh(atanh(x)) == 1 / sqrt(1 - x ** 2)

    assert tanh(asinh(x)) == x / sqrt(1 + x ** 2)
    assert tanh(acosh(x)) == sqrt(x - 1) * sqrt(x + 1) / x
    assert tanh(atanh(x)) == x

def test_issue_6746():
    y = Symbol('y')
    n = Symbol('n')
    assert manualintegrate(y**x, x) == \
        Piecewise((x, Eq(log(y), 0)), (y**x/log(y), True))
    assert manualintegrate(y**(n*x), x) == \
        Piecewise(
            (x, Eq(n, 0)),
            (Piecewise(
                (n*x, Eq(log(y), 0)),
                (y**(n*x)/log(y), True))/n, True))
    assert manualintegrate(exp(n*x), x) == \
        Piecewise((x, Eq(n, 0)), (exp(n*x)/n, True))

    y = Symbol('y', positive=True)
    assert manualintegrate((y + 1)**x, x) == (y + 1)**x/log(y + 1)
    y = Symbol('y', zero=True)
    assert manualintegrate((y + 1)**x, x) == x
    y = Symbol('y')
    n = Symbol('n', nonzero=True)
    assert manualintegrate(y**(n*x), x) == \
        Piecewise((n*x, Eq(log(y), 0)), (y**(n*x)/log(y), True))/n
    y = Symbol('y', positive=True)
    assert manualintegrate((y + 1)**(n*x), x) == \
        (y + 1)**(n*x)/(n*log(y + 1))
    a = Symbol('a', negative=True)
    assert manualintegrate(1 / (a + b*x**2), x) == \
        Piecewise((atan(x/sqrt(a/b))/(b*sqrt(a/b)), a/b > 0), \
        (-acoth(x/sqrt(-a/b))/(b*sqrt(-a/b)), And(a/b < 0, x**2 > -a/b)), \
        (-atanh(x/sqrt(-a/b))/(b*sqrt(-a/b)), And(a/b < 0, x**2 < -a/b)))

def test_derivs():
    x = Symbol('x')
    assert coth(x).diff(x) == -sinh(x)**(-2)
    assert sinh(x).diff(x) == cosh(x)
    assert cosh(x).diff(x) == sinh(x)
    assert tanh(x).diff(x) == -tanh(x)**2 + 1
    assert acoth(x).diff(x) == 1/(-x**2 + 1)
    assert asinh(x).diff(x) == 1/sqrt(x**2 + 1)
    assert acosh(x).diff(x) == 1/sqrt(x**2 - 1)
    assert atanh(x).diff(x) == 1/(-x**2 + 1)

def test_hyperbolic():
    x = Symbol("x")
    assert sinh(x).nseries(x, 0, 6) == x + x**3/6 + x**5/120 + O(x**6)
    assert cosh(x).nseries(x, 0, 5) == 1 + x**2/2 + x**4/24 + O(x**5)
    assert tanh(x).nseries(x, 0, 6) == x - x**3/3 + 2*x**5/15 + O(x**6)
    assert coth(x).nseries(x, 0, 6) == 1/x - x**3/45 + x/3 + 2*x**5/945 + O(x**6)
    assert asinh(x).nseries(x, 0, 6) == x - x**3/6 + 3*x**5/40 + O(x**6)
    assert acosh(x).nseries(x, 0, 6) == pi*I/2 - I*x - 3*I*x**5/40 - I*x**3/6 + O(x**6)
    assert atanh(x).nseries(x, 0, 6) == x + x**3/3 + x**5/5 + O(x**6)
    assert acoth(x).nseries(x, 0, 6) == x + x**3/3 + x**5/5 + pi*I/2 + O(x**6)

def test_inverses():
    x = Symbol('x')
    assert sinh(x).inverse() == asinh
    raises(AttributeError, lambda: cosh(x).inverse())
    assert tanh(x).inverse() == atanh
    assert coth(x).inverse() == acoth
    assert asinh(x).inverse() == sinh
    assert acosh(x).inverse() == cosh
    assert atanh(x).inverse() == tanh
    assert acoth(x).inverse() == coth

def test_conv12b():
    x = sympy.Symbol("x")
    y = sympy.Symbol("y")
    assert sympify(sympy.sinh(x/3)) == sinh(Symbol("x") / 3)
    assert sympify(sympy.cosh(x/3)) == cosh(Symbol("x") / 3)
    assert sympify(sympy.tanh(x/3)) == tanh(Symbol("x") / 3)
    assert sympify(sympy.coth(x/3)) == coth(Symbol("x") / 3)
    assert sympify(sympy.asinh(x/3)) == asinh(Symbol("x") / 3)
    assert sympify(sympy.acosh(x/3)) == acosh(Symbol("x") / 3)
    assert sympify(sympy.atanh(x/3)) == atanh(Symbol("x") / 3)
    assert sympify(sympy.acoth(x/3)) == acoth(Symbol("x") / 3)

def test_simplifications():
    x = Symbol('x')
    assert sinh(asinh(x)) == x
    assert sinh(acosh(x)) == sqrt(x - 1) * sqrt(x + 1)
    assert sinh(atanh(x)) == x/sqrt(1 - x**2)
    assert sinh(acoth(x)) == 1/(sqrt(x - 1) * sqrt(x + 1))

    assert cosh(asinh(x)) == sqrt(1 + x**2)
    assert cosh(acosh(x)) == x
    assert cosh(atanh(x)) == 1/sqrt(1 - x**2)
    assert cosh(acoth(x)) == x/(sqrt(x - 1) * sqrt(x + 1))

    assert tanh(asinh(x)) == x/sqrt(1 + x**2)
    assert tanh(acosh(x)) == sqrt(x - 1) * sqrt(x + 1) / x
    assert tanh(atanh(x)) == x
    assert tanh(acoth(x)) == 1/x

    assert coth(asinh(x)) == sqrt(1 + x**2)/x
    assert coth(acosh(x)) == x/(sqrt(x - 1) * sqrt(x + 1))
    assert coth(atanh(x)) == 1/x
    assert coth(acoth(x)) == x

    assert csch(asinh(x)) == 1/x
    assert csch(acosh(x)) == 1/(sqrt(x - 1) * sqrt(x + 1))
    assert csch(atanh(x)) == sqrt(1 - x**2)/x
    assert csch(acoth(x)) == sqrt(x - 1) * sqrt(x + 1)

    assert sech(asinh(x)) == 1/sqrt(1 + x**2)
    assert sech(acosh(x)) == 1/x
    assert sech(atanh(x)) == sqrt(1 - x**2)
    assert sech(acoth(x)) == sqrt(x - 1) * sqrt(x + 1)/x

def test_hyperexpand_bases():
    assert hyperexpand(hyper([2], [a], z)) == \
        a + z**(-a + 1)*(-a**2 + 3*a + z*(a - 1) - 2)*exp(z)*lowergamma(a - 1, z) - 1
    # TODO [a+1, a-S.Half], [2*a]
    assert hyperexpand(hyper([1, 2], [3], z)) == -2/z - 2*log(-z + 1)/z**2
    assert hyperexpand(hyper([S.Half, 2], [S(3)/2], z)) == \
      -1/(2*z - 2) + atanh(sqrt(z))/sqrt(z)/2
    assert hyperexpand(hyper([S(1)/2, S(1)/2], [S(5)/2], z)) == \
               (-3*z + 3)/4/(z*sqrt(-z + 1)) \
               + (6*z - 3)*asin(sqrt(z))/(4*z**(S(3)/2))
    assert hyperexpand(hyper([1, 2], [S(3)/2], z)) == -1/(2*z - 2) \
            - asin(sqrt(z))/(sqrt(z)*(2*z - 2)*sqrt(-z + 1))
    assert hyperexpand(hyper([-S.Half - 1, 1, 2], [S.Half, 3], z)) == \
             sqrt(z)*(6*z/7 - S(6)/5)*atanh(sqrt(z)) \
           + (-30*z**2 + 32*z - 6)/35/z - 6*log(-z + 1)/(35*z**2)
    assert hyperexpand(hyper([1+S.Half, 1, 1], [2, 2], z)) == \
           -4*log(sqrt(-z + 1)/2 + S(1)/2)/z
    # TODO hyperexpand(hyper([a], [2*a + 1], z))
    # TODO [S.Half, a], [S(3)/2, a+1]
    assert hyperexpand(hyper([2], [b, 1], z)) == \
             z**(-b/2 + S(1)/2)*besseli(b - 1, 2*sqrt(z))*gamma(b) \
           + z**(-b/2 + 1)*besseli(b, 2*sqrt(z))*gamma(b)

def test_atanh():
    # TODO please write more tests  -- see #652
    # From http://functions.wolfram.com/ElementaryFunctions/ArcTanh/03/01/
    # at specific points
    x = Symbol('x')

    #at specific points
    assert atanh(0) == 0
    assert atanh(I) == I*pi/4
    assert atanh(-I) == -I*pi/4
    assert atanh(1) == oo
    assert atanh(-1) == -oo

    # at infinites
    assert atanh(I*oo) == I*pi/2
    assert atanh(-I*oo) == -I*pi/2

    #properties
    assert atanh(-x) == -atanh(x)

def test_derivs():
    x = Symbol('x')
    assert coth(x).diff(x) == -sinh(x)**(-2)
    assert sinh(x).diff(x) == cosh(x)
    assert cosh(x).diff(x) == sinh(x)
    assert tanh(x).diff(x) == -tanh(x)**2 + 1
    assert csch(x).diff(x) == -coth(x)*csch(x)
    assert sech(x).diff(x) == -tanh(x)*sech(x)
    assert acoth(x).diff(x) == 1/(-x**2 + 1)
    assert asinh(x).diff(x) == 1/sqrt(x**2 + 1)
    assert acosh(x).diff(x) == 1/sqrt(x**2 - 1)
    assert atanh(x).diff(x) == 1/(-x**2 + 1)
    assert asech(x).diff(x) == -1/(x*sqrt(1 - x**2))
    assert acsch(x).diff(x) == -1/(x**2*sqrt(1 + x**(-2)))

def test_atan():
    assert atan(nan) == nan

    assert atan(oo) == pi/2
    assert atan(-oo) == -pi/2

    assert atan(0) == 0
    assert atan(1) == pi/4
    assert atan(sqrt(3)) == pi/3
    assert atan(oo) == pi/2
    assert atan(x).diff(x) == 1/(1 + x**2)

    assert atan(r).is_real is True

    assert atan(-2*I) == -I*atanh(2)

def test_P():
    assert P(0, z, m) == F(z, m)
    assert P(1, z, m) == F(z, m) + (sqrt(1 - m * sin(z) ** 2) * tan(z) - E(z, m)) / (1 - m)
    assert P(n, i * pi / 2, m) == i * P(n, m)
    assert P(n, z, 0) == atanh(sqrt(n - 1) * tan(z)) / sqrt(n - 1)
    assert P(n, z, n) == F(z, n) - P(1, z, n) + tan(z) / sqrt(1 - n * sin(z) ** 2)
    assert P(oo, z, m) == 0
    assert P(-oo, z, m) == 0
    assert P(n, z, oo) == 0
    assert P(n, z, -oo) == 0
    assert P(0, m) == K(m)
    assert P(1, m) == zoo
    assert P(n, 0) == pi / (2 * sqrt(1 - n))
    assert P(2, 1) == -oo
    assert P(-1, 1) == oo
    assert P(n, n) == E(n) / (1 - n)

    assert P(n, -z, m) == -P(n, z, m)

    ni, mi = Symbol("n", real=False), Symbol("m", real=False)
    assert P(ni, z, mi).conjugate() == P(ni.conjugate(), z.conjugate(), mi.conjugate())
    nr, mr = Symbol("n", real=True, negative=True), Symbol("m", real=True, negative=True)
    assert P(nr, z, mr).conjugate() == P(nr, z.conjugate(), mr)
    assert P(n, m).conjugate() == P(n.conjugate(), m.conjugate())

    assert P(n, z, m).diff(n) == (
        E(z, m)
        + (m - n) * F(z, m) / n
        + (n ** 2 - m) * P(n, z, m) / n
        - n * sqrt(1 - m * sin(z) ** 2) * sin(2 * z) / (2 * (1 - n * sin(z) ** 2))
    ) / (2 * (m - n) * (n - 1))
    assert P(n, z, m).diff(z) == 1 / (sqrt(1 - m * sin(z) ** 2) * (1 - n * sin(z) ** 2))
    assert P(n, z, m).diff(m) == (
        E(z, m) / (m - 1) + P(n, z, m) - m * sin(2 * z) / (2 * (m - 1) * sqrt(1 - m * sin(z) ** 2))
    ) / (2 * (n - m))
    assert P(n, m).diff(n) == (E(m) + (m - n) * K(m) / n + (n ** 2 - m) * P(n, m) / n) / (2 * (m - n) * (n - 1))
    assert P(n, m).diff(m) == (E(m) / (m - 1) + P(n, m)) / (2 * (n - m))
    rx, ry = randcplx(), randcplx()
    assert td(P(n, rx, ry), n)
    assert td(P(rx, z, ry), z)
    assert td(P(rx, ry, m), m)

    assert P(n, z, m).series(z) == z + z ** 3 * (m / 6 + n / 3) + z ** 5 * (
        3 * m ** 2 / 40 + m * n / 10 - m / 30 + n ** 2 / 5 - n / 15
    ) + O(z ** 6)