示例#1
0
def test_K():
    assert K(0) == pi / 2
    assert K(S(1) / 2) == 8 * pi ** (S(3) / 2) / gamma(-S(1) / 4) ** 2
    assert K(1) == zoo
    assert K(-1) == gamma(S(1) / 4) ** 2 / (4 * sqrt(2 * pi))
    assert K(oo) == 0
    assert K(-oo) == 0
    assert K(I * oo) == 0
    assert K(-I * oo) == 0
    assert K(zoo) == 0

    assert K(z).diff(z) == (E(z) - (1 - z) * K(z)) / (2 * z * (1 - z))
    assert td(K(z), z)

    zi = Symbol("z", real=False)
    assert K(zi).conjugate() == K(zi.conjugate())
    zr = Symbol("z", real=True, negative=True)
    assert K(zr).conjugate() == K(zr)

    assert K(z).rewrite(hyper) == (pi / 2) * hyper((S.Half, S.Half), (S.One,), z)
    assert tn(K(z), (pi / 2) * hyper((S.Half, S.Half), (S.One,), z))
    assert K(z).rewrite(meijerg) == meijerg(((S.Half, S.Half), []), ((S.Zero,), (S.Zero,)), -z) / 2
    assert tn(K(z), meijerg(((S.Half, S.Half), []), ((S.Zero,), (S.Zero,)), -z) / 2)

    assert K(z).series(
        z
    ) == pi / 2 + pi * z / 8 + 9 * pi * z ** 2 / 128 + 25 * pi * z ** 3 / 512 + 1225 * pi * z ** 4 / 32768 + 3969 * pi * z ** 5 / 131072 + O(
        z ** 6
    )
示例#2
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def test_cosine_transform():
    from sympy import sinh, cosh, Si, Ci

    t = symbols("t")
    w = symbols("w")
    a = symbols("a")
    f = Function("f")

    # Test unevaluated form
    assert cosine_transform(f(t), t, w) == CosineTransform(f(t), t, w)
    assert inverse_cosine_transform(f(w), w, t) == InverseCosineTransform(f(w), w, t)

    assert cosine_transform(1/sqrt(t), t, w) == 1/sqrt(w)
    assert inverse_cosine_transform(1/sqrt(w), w, t) == 1/sqrt(t)

    assert cosine_transform(1/(a**2+t**2), t, w) == sqrt(2)*sqrt(pi)*(-sinh(a*w) + cosh(a*w))/(2*a)

    assert cosine_transform(t**(-a), t, w) == 2**(-a + S(1)/2)*w**(a - 1)*gamma((-a + 1)/2)/gamma(a/2)
    assert inverse_cosine_transform(2**(-a + S(1)/2)*w**(a - 1)*gamma(-a/2 + S(1)/2)/gamma(a/2), w, t) == t**(-a)

    assert cosine_transform(exp(-a*t), t, w) == sqrt(2)*a/(sqrt(pi)*(a**2 + w**2))
    assert inverse_cosine_transform(sqrt(2)*a/(sqrt(pi)*(a**2 + w**2)), w, t) == -sinh(a*t) + cosh(a*t)

    assert cosine_transform(exp(-a*sqrt(t))*cos(a*sqrt(t)), t, w) == a*(-sinh(a**2/(2*w)) + cosh(a**2/(2*w)))/(2*w**(S(3)/2))

    assert cosine_transform(1/(a+t), t, w) == -sqrt(2)*((2*Si(a*w) - pi)*sin(a*w) + 2*cos(a*w)*Ci(a*w))/(2*sqrt(pi))
    assert inverse_cosine_transform(sqrt(2)*meijerg(((S(1)/2, 0), ()), ((S(1)/2, 0, 0), (S(1)/2,)), a**2*w**2/4)/(2*pi), w, t) == 1/(a + t)

    assert cosine_transform(1/sqrt(a**2+t**2), t, w) == sqrt(2)*meijerg(((S(1)/2,), ()), ((0, 0), (S(1)/2,)), a**2*w**2/4)/(2*sqrt(pi))
    assert inverse_cosine_transform(sqrt(2)*meijerg(((S(1)/2,), ()), ((0, 0), (S(1)/2,)), a**2*w**2/4)/(2*sqrt(pi)), w, t) == 1/(t*sqrt(a**2/t**2 + 1))
示例#3
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def test_E():
    assert E(z, 0) == z
    assert E(0, m) == 0
    assert E(i*pi/2, m) == i*E(m)
    assert E(z, oo) == zoo
    assert E(z, -oo) == zoo
    assert E(0) == pi/2
    assert E(1) == 1
    assert E(oo) == I*oo
    assert E(-oo) == oo
    assert E(zoo) == zoo

    assert E(-z, m) == -E(z, m)

    assert E(z, m).diff(z) == sqrt(1 - m*sin(z)**2)
    assert E(z, m).diff(m) == (E(z, m) - F(z, m))/(2*m)
    assert E(z).diff(z) == (E(z) - K(z))/(2*z)
    r = randcplx()
    assert td(E(r, m), m)
    assert td(E(z, r), z)
    assert td(E(z), z)

    mi = Symbol('m', real=False)
    assert E(z, mi).conjugate() == E(z.conjugate(), mi.conjugate())
    mr = Symbol('m', real=True, negative=True)
    assert E(z, mr).conjugate() == E(z.conjugate(), mr)

    assert E(z).rewrite(hyper) == (pi/2)*hyper((-S.Half, S.Half), (S.One,), z)
    assert tn(E(z), (pi/2)*hyper((-S.Half, S.Half), (S.One,), z))
    assert E(z).rewrite(meijerg) == \
        -meijerg(((S.Half, S(3)/2), []), ((S.Zero,), (S.Zero,)), -z)/4
    assert tn(E(z), -meijerg(((S.Half, S(3)/2), []), ((S.Zero,), (S.Zero,)), -z)/4)
示例#4
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def test_meijerg_eval():
    from sympy import besseli, exp_polar
    from sympy.abc import l
    a = randcplx()
    arg = x*exp_polar(k*pi*I)
    expr1 = pi*meijerg([[], [(a + 1)/2]], [[a/2], [-a/2, (a + 1)/2]], arg**2/4)
    expr2 = besseli(a, arg)

    # Test that the two expressions agree for all arguments.
    for x_ in [0.5, 1.5]:
        for k_ in [0.0, 0.1, 0.3, 0.5, 0.8, 1, 5.751, 15.3]:
            assert abs((expr1 - expr2).n(subs={x: x_, k: k_})) < 1e-10
            assert abs((expr1 - expr2).n(subs={x: x_, k: -k_})) < 1e-10

    # Test continuity independently
    eps = 1e-13
    expr2 = expr1.subs(k, l)
    for x_ in [0.5, 1.5]:
        for k_ in [0.5, S(1)/3, 0.25, 0.75, S(2)/3, 1.0, 1.5]:
            assert abs((expr1 - expr2).n(
                       subs={x: x_, k: k_ + eps, l: k_ - eps})) < 1e-10
            assert abs((expr1 - expr2).n(
                       subs={x: x_, k: -k_ + eps, l: -k_ - eps})) < 1e-10

    expr = (meijerg(((0.5,), ()), ((0.5, 0, 0.5), ()), exp_polar(-I*pi)/4)
            + meijerg(((0.5,), ()), ((0.5, 0, 0.5), ()), exp_polar(I*pi)/4)) \
        /(2*sqrt(pi))
    assert (expr - pi/exp(1)).n(chop=True) == 0
示例#5
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def test_K():
    assert K(0) == pi/2
    assert K(S(1)/2) == 8*pi**(S(3)/2)/gamma(-S(1)/4)**2
    assert K(1) == zoo
    assert K(-1) == gamma(S(1)/4)**2/(4*sqrt(2*pi))
    assert K(oo) == 0
    assert K(-oo) == 0
    assert K(I*oo) == 0
    assert K(-I*oo) == 0
    assert K(zoo) == 0

    assert K(z).diff(z) == (E(z) - (1 - z)*K(z))/(2*z*(1 - z))
    assert td(K(z), z)

    zi = Symbol('z', real=False)
    assert K(zi).conjugate() == K(zi.conjugate())
    zr = Symbol('z', real=True, negative=True)
    assert K(zr).conjugate() == K(zr)

    assert K(z).rewrite(hyper) == \
        (pi/2)*hyper((S.Half, S.Half), (S.One,), z)
    assert tn(K(z), (pi/2)*hyper((S.Half, S.Half), (S.One,), z))
    assert K(z).rewrite(meijerg) == \
        meijerg(((S.Half, S.Half), []), ((S.Zero,), (S.Zero,)), -z)/2
    assert tn(K(z), meijerg(((S.Half, S.Half), []), ((S.Zero,), (S.Zero,)), -z)/2)
示例#6
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def test_rewrite1():
    assert _rewrite1(x ** 3 * meijerg([a], [b], [c], [d], x ** 2 + y * x ** 2) * 5, x) == (
        5,
        x ** 3,
        [(1, 0, meijerg([a], [b], [c], [d], x ** 2 * (y + 1)))],
        True,
    )
示例#7
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def can_do_meijer(a1, a2, b1, b2, numeric=True):
    """
    This helper function tries to hyperexpand() the meijer g-function
    corresponding to the parameters a1, a2, b1, b2.
    It returns False if this expansion still contains g-functions.
    If numeric is True, it also tests the so-obtained formula numerically
    (at random values) and returns False if the test fails.
    Else it returns True.
    """
    from sympy import unpolarify, expand
    r = hyperexpand(meijerg(a1, a2, b1, b2, z))
    if r.has(meijerg):
        return False
    # NOTE hyperexpand() returns a truly branched function, whereas numerical
    #      evaluation only works on the main branch. Since we are evaluating on
    #      the main branch, this should not be a problem, but expressions like
    #      exp_polar(I*pi/2*x)**a are evaluated incorrectly. We thus have to get
    #      rid of them. The expand heuristically does this...
    r = unpolarify(expand(r, force=True, power_base=True, power_exp=False,
                          mul=False, log=False, multinomial=False, basic=False))

    if not numeric:
        return True

    repl = {}
    for n, a in enumerate(meijerg(a1, a2, b1, b2, z).free_symbols - set([z])):
        repl[a] = randcplx(n)
    return tn(meijerg(a1, a2, b1, b2, z).subs(repl), r.subs(repl), z)
示例#8
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def test_issue_10798():
    from sympy import integrate, pi, I, log, polylog, exp_polar, Piecewise, meijerg, Abs
    from sympy.abc import x, y
    assert integrate(1/(1-(x*y)**2), (x, 0, 1), y) == \
        -Piecewise((I*pi*log(y) - polylog(2, y), Abs(y) < 1), (-I*pi*log(1/y) - polylog(2, y), Abs(1/y) < 1), \
                   (-I*pi*meijerg(((), (1, 1)), ((0, 0), ()), y) + I*pi*meijerg(((1, 1), ()), ((), (0, 0)), y) - polylog(2, y), True))/2 \
                   - log(y)*log(1 - 1/y)/2 + log(y)*log(1 + 1/y)/2 + log(y)*log(y - 1)/2 \
                   - log(y)*log(y + 1)/2 + I*pi*log(y)/2 - polylog(2, y*exp_polar(I*pi))/2
示例#9
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def test_meijerg_lookup():
    from sympy import uppergamma

    assert hyperexpand(meijerg([a], [], [b, a], [], z)) == z ** b * exp(z) * gamma(-a + b + 1) * uppergamma(a - b, z)
    assert hyperexpand(meijerg([0], [], [0, 0], [], z)) == exp(z) * uppergamma(0, z)
    assert can_do_meijer([a], [], [b, a + 1], [])
    assert can_do_meijer([a], [], [b + 2, a], [])
    assert can_do_meijer([a], [], [b - 2, a], [])
示例#10
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def test_limits():
    k, x = symbols('k, x')
    assert hyper((1,), (S(4)/3, S(5)/3), k**2).series(k) == \
           hyper((1,), (S(4)/3, S(5)/3), 0) + \
           9*k**2*hyper((2,), (S(7)/3, S(8)/3), 0)/20 + \
           81*k**4*hyper((3,), (S(10)/3, S(11)/3), 0)/1120 + \
           O(k**6) # issue 6350
    assert limit(meijerg((), (), (1,), (0,), -x), x, 0) == \
            meijerg(((), ()), ((1,), (0,)), 0) # issue 6052
示例#11
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def test_meijerint():
    from sympy import symbols, expand, arg

    s, t, mu = symbols("s t mu", real=True)
    assert integrate(
        meijerg([], [], [0], [], s * t) * meijerg([], [], [mu / 2], [-mu / 2], t ** 2 / 4), (t, 0, oo)
    ).is_Piecewise
    s = symbols("s", positive=True)
    assert integrate(x ** s * meijerg([[], []], [[0], []], x), (x, 0, oo)) == gamma(s + 1)
    assert integrate(x ** s * meijerg([[], []], [[0], []], x), (x, 0, oo), meijerg=True) == gamma(s + 1)
    assert isinstance(integrate(x ** s * meijerg([[], []], [[0], []], x), (x, 0, oo), meijerg=False), Integral)

    assert meijerint_indefinite(exp(x), x) == exp(x)

    # TODO what simplifications should be done automatically?
    # This tests "extra case" for antecedents_1.
    a, b = symbols("a b", positive=True)
    assert simplify(meijerint_definite(x ** a, x, 0, b)[0]) == b ** (a + 1) / (a + 1)

    # This tests various conditions and expansions:
    meijerint_definite((x + 1) ** 3 * exp(-x), x, 0, oo) == (16, True)

    # Again, how about simplifications?
    sigma, mu = symbols("sigma mu", positive=True)
    i, c = meijerint_definite(exp(-((x - mu) / (2 * sigma)) ** 2), x, 0, oo)
    assert simplify(i) == sqrt(pi) * sigma * (erf(mu / (2 * sigma)) + 1)
    assert c is True

    i, _ = meijerint_definite(exp(-mu * x) * exp(sigma * x), x, 0, oo)
    # TODO it would be nice to test the condition
    assert simplify(i) == 1 / (mu - sigma)

    # Test substitutions to change limits
    assert meijerint_definite(exp(x), x, -oo, 2) == (exp(2), True)
    assert expand(meijerint_definite(exp(x), x, 0, I)[0]) == exp(I) - 1
    assert expand(meijerint_definite(exp(-x), x, 0, x)[0]) == 1 - exp(-exp(I * arg(x)) * abs(x))

    # Test -oo to oo
    assert meijerint_definite(exp(-x ** 2), x, -oo, oo) == (sqrt(pi), True)
    assert meijerint_definite(exp(-abs(x)), x, -oo, oo) == (2, True)
    assert meijerint_definite(exp(-(2 * x - 3) ** 2), x, -oo, oo) == (sqrt(pi) / 2, True)
    assert meijerint_definite(exp(-abs(2 * x - 3)), x, -oo, oo) == (1, True)
    assert meijerint_definite(exp(-((x - mu) / sigma) ** 2 / 2) / sqrt(2 * pi * sigma ** 2), x, -oo, oo) == (1, True)

    # Test one of the extra conditions for 2 g-functinos
    assert meijerint_definite(exp(-x) * sin(x), x, 0, oo) == (S(1) / 2, True)

    # Test a bug
    def res(n):
        return (1 / (1 + x ** 2)).diff(x, n).subs(x, 1) * (-1) ** n

    for n in range(6):
        assert integrate(exp(-x) * sin(x) * x ** n, (x, 0, oo), meijerg=True) == res(n)

    # Test trigexpand:
    assert integrate(exp(-x) * sin(x + a), (x, 0, oo), meijerg=True) == sin(a) / 2 + cos(a) / 2
示例#12
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def test_meijerg_shift_operators():
    # carefully set up the parameters. XXX this still fails sometimes
    a1, a2, a3, a4, a5, b1, b2, b3, b4, b5 = \
        map(lambda n: randcplx(n), range(10))
    g = meijerg([a1], [a3, a4], [b1], [b3, b4], z)

    assert tn(MeijerShiftA(b1).apply(g, op),
              meijerg([a1], [a3, a4], [b1 + 1], [b3, b4], z), z)
    assert tn(MeijerShiftB(a1).apply(g, op),
              meijerg([a1 - 1], [a3, a4], [b1], [b3, b4], z), z)
    assert tn(MeijerShiftC(b3).apply(g, op),
              meijerg([a1], [a3, a4], [b1], [b3 + 1, b4], z), z)
    assert tn(MeijerShiftD(a3).apply(g, op),
              meijerg([a1], [a3 - 1, a4], [b1], [b3, b4], z), z)

    s = MeijerUnShiftA([a1], [a3, a4], [b1], [b3, b4], 0, z)
    assert tn(
        s.apply(g, op), meijerg([a1], [a3, a4], [b1 - 1], [b3, b4], z), z)

    s = MeijerUnShiftC([a1], [a3, a4], [b1], [b3, b4], 0, z)
    assert tn(
        s.apply(g, op), meijerg([a1], [a3, a4], [b1], [b3 - 1, b4], z), z)

    s = MeijerUnShiftB([a1], [a3, a4], [b1], [b3, b4], 0, z)
    assert tn(
        s.apply(g, op), meijerg([a1 + 1], [a3, a4], [b1], [b3, b4], z), z)

    s = MeijerUnShiftD([a1], [a3, a4], [b1], [b3, b4], 0, z)
    assert tn(
        s.apply(g, op), meijerg([a1], [a3 + 1, a4], [b1], [b3, b4], z), z)
示例#13
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def test_meijerg():
    expr = meijerg([pi, pi, x], [1], [0, 1], [1, 2, 3], z)
    ucode_str = \
u"""\
╭─╮2, 3 ⎛π, π, x     1    │  ⎞\n\
│╶┐     ⎜                 │ z⎟\n\
╰─╯4, 5 ⎝ 0, 1    1, 2, 3 │  ⎠\
"""
    ascii_str = \
"""\
 __2, 3 /pi, pi, x     1    |  \\\n\
/__     |                   | z|\n\
\_|4, 5 \\  0, 1     1, 2, 3 |  /\
"""
    assert pretty(expr) == ascii_str
    assert upretty(expr) == ucode_str

    expr = meijerg([1, pi/7], [2, pi, 5], [], [], z**2)
    ucode_str = \
u"""\
        ⎛   π          │   ⎞\n\
╭─╮0, 2 ⎜1, ─  2, π, 5 │  2⎟\n\
│╶┐     ⎜   7          │ z ⎟\n\
╰─╯5, 0 ⎜              │   ⎟\n\
        ⎝              │   ⎠\
"""
    ascii_str = \
"""\
        /   pi           |   \\\n\
 __0, 2 |1, --  2, pi, 5 |  2|\n\
/__     |   7            | z |\n\
\_|5, 0 |                |   |\n\
        \\                |   /\
"""
    assert pretty(expr) == ascii_str
    assert upretty(expr) == ucode_str


    ucode_str = \
u"""\
╭─╮ 1, 10 ⎛1, 1, 1, 1, 1, 1, 1, 1, 1, 1  1 │  ⎞\n\
│╶┐       ⎜                                │ z⎟\n\
╰─╯11,  2 ⎝             1                1 │  ⎠\
"""
    ascii_str = \
"""\
 __ 1, 10 /1, 1, 1, 1, 1, 1, 1, 1, 1, 1  1 |  \\\n\
/__       |                                | z|\n\
\_|11,  2 \\             1                1 |  /\
"""

    expr = meijerg([1]*10, [1], [1], [1], z)
    assert pretty(expr) == ascii_str
    assert upretty(expr) == ucode_str
示例#14
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def test_gh_issue_2711():
    x = Symbol('x')
    f = meijerg(((), ()), ((0,), ()), x)
    a = Wild('a')
    b = Wild('b')

    assert f.find(a) == set([(S.Zero,), ((), ()), ((S.Zero,), ()), x, S.Zero,
                             (), meijerg(((), ()), ((S.Zero,), ()), x)])
    assert f.find(a + b) == \
        {meijerg(((), ()), ((S.Zero,), ()), x), x, S.Zero}
    assert f.find(a**2) == {meijerg(((), ()), ((S.Zero,), ()), x), x}
示例#15
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def test_expand_func():
    # evaluation at 1 of Gauss' hypergeometric function:
    from sympy.abc import a, b, c
    from sympy import gamma, expand_func

    a1, b1, c1 = randcplx(), randcplx(), randcplx() + 5
    assert expand_func(hyper([a, b], [c], 1)) == gamma(c) * gamma(-a - b + c) / (gamma(-a + c) * gamma(-b + c))
    assert abs(expand_func(hyper([a1, b1], [c1], 1)).n() - hyper([a1, b1], [c1], 1).n()) < 1e-10

    # hyperexpand wrapper for hyper:
    assert expand_func(hyper([], [], z)) == exp(z)
    assert expand_func(hyper([1, 2, 3], [], z)) == hyper([1, 2, 3], [], z)
    assert expand_func(meijerg([[1, 1], []], [[1], [0]], z)) == log(z + 1)
    assert expand_func(meijerg([[1, 1], []], [[], []], z)) == meijerg([[1, 1], []], [[], []], z)
示例#16
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def test_hyper_printing():
    from sympy import pi, Tuple
    from sympy.abc import x, z

    assert latex(meijerg(Tuple(pi, pi, x), Tuple(1), \
                         (0,1), Tuple(1, 2, 3/pi),z)) == \
             r'{G_{4, 5}^{2, 3}\left.\left(\begin{matrix} \pi, \pi, x & 1 \\0, 1 & 1, 2, \frac{3}{\pi} \end{matrix} \right| {z} \right)}'
    assert latex(meijerg(Tuple(), Tuple(1), (0,), Tuple(),z)) == \
             r'{G_{1, 1}^{1, 0}\left.\left(\begin{matrix}  & 1 \\0 &  \end{matrix} \right| {z} \right)}'
    assert latex(hyper((x, 2), (3,), z)) == \
               r'{{}_{2}F_{1}\left.\left(\begin{matrix} x, 2 ' \
               r'\\ 3 \end{matrix}\right| {z} \right)}'
    assert latex(hyper(Tuple(), Tuple(1), z)) == \
               r'{{}_{0}F_{1}\left.\left(\begin{matrix}  ' \
               r'\\ 1 \end{matrix}\right| {z} \right)}'
示例#17
0
def test_meijerg_lookup():
    from sympy import uppergamma, Si, Ci
    assert hyperexpand(meijerg([a], [], [b, a], [], z)) == \
        z**b*exp(z)*gamma(-a + b + 1)*uppergamma(a - b, z)
    assert hyperexpand(meijerg([0], [], [0, 0], [], z)) == \
        exp(z)*uppergamma(0, z)
    assert can_do_meijer([a], [], [b, a + 1], [])
    assert can_do_meijer([a], [], [b + 2, a], [])
    assert can_do_meijer([a], [], [b - 2, a], [])

    assert hyperexpand(meijerg([a], [], [a, a, a - S(1)/2], [], z)) == \
        -sqrt(pi)*z**(a - S(1)/2)*(2*cos(2*sqrt(z))*(Si(2*sqrt(z)) - pi/2)
                                   - 2*sin(2*sqrt(z))*Ci(2*sqrt(z))) == \
        hyperexpand(meijerg([a], [], [a, a - S(1)/2, a], [], z)) == \
        hyperexpand(meijerg([a], [], [a - S(1)/2, a, a], [], z))
    assert can_do_meijer([a - 1], [], [a + 2, a - S(3)/2, a + 1], [])
示例#18
0
def test_branch_bug():
    assert hyperexpand(hyper((-S(1)/3, S(1)/2), (S(2)/3, S(3)/2), -z)) == \
        -z**S('1/3')*lowergamma(exp_polar(I*pi)/3, z)/5 \
        + sqrt(pi)*erf(sqrt(z))/(5*sqrt(z))
    assert hyperexpand(meijerg([S(7)/6, 1], [], [S(2)/3], [S(1)/6, 0], z)) == \
        2*z**S('2/3')*(2*sqrt(pi)*erf(sqrt(z))/sqrt(z) - 2*lowergamma(
                       S(2)/3, z)/z**S('2/3'))*gamma(S(2)/3)/gamma(S(5)/3)
示例#19
0
def test_meijerg_with_Floats():
    # see issue #10681
    from sympy import RR
    f = meijerg(((3.0, 1), ()), ((S(3)/2,), (0,)), z)
    a = -2.3632718012073
    g = a*z**(S(3)/2)*hyper((-0.5, S(3)/2), (S(5)/2,), z*exp_polar(I*pi))
    assert RR.almosteq((hyperexpand(f)/g).n(), 1.0, 1e-12)
示例#20
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def test_from_meijerg():
    x = symbols('x')
    R, Dx = DifferentialOperators(QQ.old_poly_ring(x), 'Dx')
    p = from_meijerg(meijerg(([], [S(3)/2]), ([S(1)/2], [S(1)/2, 1]), x))
    q = HolonomicFunction(x/2 - 1/4 + (-x**2 + x/4)*Dx + x**2*Dx**2 + x**3*Dx**3, x, 1, \
        [1/sqrt(pi), 1/(2*sqrt(pi)), -1/(4*sqrt(pi))])
    assert p == q
    p = from_meijerg(meijerg(([], []), ([0], []), x))
    q = HolonomicFunction(1 + Dx, x, 0, [1])
    assert p == q
    p = from_meijerg(meijerg(([1], []), ([S(1)/2], [0]), x))
    q = HolonomicFunction((x + 1/2)*Dx + x*Dx**2, x, 1, [sqrt(pi)*erf(1), exp(-1)])
    assert p == q
    p = from_meijerg(meijerg(([0], [1]), ([0], []), 2*x**2))
    q = HolonomicFunction((3*x**2 - 1)*Dx + x**3*Dx**2, x, 1, [-exp(-S(1)/2) + 1, -exp(-S(1)/2)])
    assert p == q
示例#21
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def test_uppergamma():
    from sympy import meijerg, exp_polar, I, expint
    assert uppergamma(4, 0) == 6
    assert uppergamma(x, y).diff(y) == -y**(x-1)*exp(-y)
    assert td(uppergamma(randcplx(), y), y)
    assert uppergamma(x, y).diff(x) == \
           uppergamma(x, y)*log(y) + meijerg([], [1, 1], [0, 0, x], [], y)
    assert td(uppergamma(x, randcplx()), x)

    assert uppergamma(S.Half, x) == sqrt(pi)*(1 - erf(sqrt(x)))
    assert not uppergamma(S.Half - 3, x).has(uppergamma)
    assert not uppergamma(S.Half + 3, x).has(uppergamma)
    assert uppergamma(S.Half, x, evaluate=False).has(uppergamma)
    assert tn(uppergamma(S.Half + 3, x, evaluate=False),
              uppergamma(S.Half + 3, x), x)
    assert tn(uppergamma(S.Half - 3, x, evaluate=False),
              uppergamma(S.Half - 3, x), x)

    assert uppergamma(x, y).rewrite(lowergamma) == gamma(x) - lowergamma(x, y)

    assert tn_branch(-3, uppergamma)
    assert tn_branch(-4, uppergamma)
    assert tn_branch(S(1)/3, uppergamma)
    assert tn_branch(pi, uppergamma)
    assert uppergamma(3, exp_polar(4*pi*I)*x) == uppergamma(3, x)
    assert uppergamma(y, exp_polar(5*pi*I)*x) == \
           exp(4*I*pi*y)*uppergamma(y, x*exp_polar(pi*I)) + gamma(y)*(1-exp(4*pi*I*y))
    assert uppergamma(-2, exp_polar(5*pi*I)*x) == \
           uppergamma(-2, x*exp_polar(I*pi)) - 2*pi*I

    assert uppergamma(-2, x) == expint(3, x)/x**2
    assert uppergamma(x, y).rewrite(expint) == y**x*expint(-x + 1, y)
示例#22
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def test_lowergamma():
    from sympy import meijerg, exp_polar, I, expint
    assert lowergamma(x, y).diff(y) == y**(x-1)*exp(-y)
    assert td(lowergamma(randcplx(), y), y)
    assert lowergamma(x, y).diff(x) == \
           gamma(x)*polygamma(0, x) - uppergamma(x, y)*log(y) \
           + meijerg([], [1, 1], [0, 0, x], [], y)

    assert lowergamma(S.Half, x) == sqrt(pi)*erf(sqrt(x))
    assert not lowergamma(S.Half - 3, x).has(lowergamma)
    assert not lowergamma(S.Half + 3, x).has(lowergamma)
    assert lowergamma(S.Half, x, evaluate=False).has(lowergamma)
    assert tn(lowergamma(S.Half + 3, x, evaluate=False),
              lowergamma(S.Half + 3, x), x)
    assert tn(lowergamma(S.Half - 3, x, evaluate=False),
              lowergamma(S.Half - 3, x), x)

    assert lowergamma(x, y).rewrite(uppergamma) == gamma(x) - uppergamma(x, y)

    assert tn_branch(-3, lowergamma)
    assert tn_branch(-4, lowergamma)
    assert tn_branch(S(1)/3, lowergamma)
    assert tn_branch(pi, lowergamma)
    assert lowergamma(3, exp_polar(4*pi*I)*x) == lowergamma(3, x)
    assert lowergamma(y, exp_polar(5*pi*I)*x) == \
           exp(4*I*pi*y)*lowergamma(y, x*exp_polar(pi*I))
    assert lowergamma(-2, exp_polar(5*pi*I)*x) == \
           lowergamma(-2, x*exp_polar(I*pi)) + 2*pi*I

    assert lowergamma(x, y).rewrite(expint) == -y**x*expint(-x + 1, y) + gamma(x)
    k = Symbol('k', integer=True)
    assert lowergamma(k, y).rewrite(expint) == -y**k*expint(-k + 1, y) + gamma(k)
    k = Symbol('k', integer=True, positive=False)
    assert lowergamma(k, y).rewrite(expint) == lowergamma(k, y)
示例#23
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 def t(fac, arg):
     g = meijerg([a], [b], [c], [d], arg)*fac
     subs = {a: randcplx()/10, b: randcplx()/10 + I,
             c: randcplx(), d: randcplx()}
     integral = meijerint_indefinite(g, x)
     assert integral is not None
     assert verify_numerically(g.subs(subs), integral.diff(x).subs(subs), x)
示例#24
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 def t(a, b, arg, n):
     from sympy import Mul
     m1 = meijerg(a, b, arg)
     m2 = Mul(*_inflate_g(m1, n))
     # NOTE: (the random number)**9 must still be on the principal sheet.
     # Thus make b&d small to create random numbers of small imaginary part.
     return verify_numerically(m1.subs(subs), m2.subs(subs), x, b=0.1, d=-0.1)
示例#25
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def test_issue_8368():
    assert integrate(exp(-s*x)*cosh(x), (x, 0, oo)) == \
        Piecewise(
            (   pi*Piecewise(
                    (   -s/(pi*(-s**2 + 1)),
                        Abs(s**2) < 1),
                    (   1/(pi*s*(1 - 1/s**2)),
                        Abs(s**(-2)) < 1),
                    (   meijerg(
                            ((S(1)/2,), (0, 0)),
                            ((0, S(1)/2), (0,)),
                            polar_lift(s)**2),
                        True)
                ),
                And(
                    Abs(periodic_argument(polar_lift(s)**2, oo)) < pi,
                    cos(Abs(periodic_argument(polar_lift(s)**2, oo))/2)*sqrt(Abs(s**2)) - 1 > 0,
                    Ne(s**2, 1))
            ),
            (
                Integral(exp(-s*x)*cosh(x), (x, 0, oo)),
                True))
    assert integrate(exp(-s*x)*sinh(x), (x, 0, oo)) == \
        Piecewise(
            (   -1/(s + 1)/2 - 1/(-s + 1)/2,
                And(
                    Ne(1/s, 1),
                    Abs(periodic_argument(s, oo)) < pi/2,
                    Abs(periodic_argument(s, oo)) <= pi/2,
                    cos(Abs(periodic_argument(s, oo)))*Abs(s) - 1 > 0)),
            (   Integral(exp(-s*x)*sinh(x), (x, 0, oo)),
                True))
示例#26
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def test_expint():
    assert mytn(expint(x, y), expint(x, y).rewrite(uppergamma), y ** (x - 1) * uppergamma(1 - x, y), x)
    assert mytd(expint(x, y), -y ** (x - 1) * meijerg([], [1, 1], [0, 0, 1 - x], [], y), x)
    assert mytd(expint(x, y), -expint(x - 1, y), y)
    assert mytn(expint(1, x), expint(1, x).rewrite(Ei), -Ei(x * polar_lift(-1)) + I * pi, x)

    assert (
        expint(-4, x)
        == exp(-x) / x + 4 * exp(-x) / x ** 2 + 12 * exp(-x) / x ** 3 + 24 * exp(-x) / x ** 4 + 24 * exp(-x) / x ** 5
    )
    assert expint(-S(3) / 2, x) == exp(-x) / x + 3 * exp(-x) / (2 * x ** 2) - 3 * sqrt(pi) * erf(sqrt(x)) / (
        4 * x ** S("5/2")
    ) + 3 * sqrt(pi) / (4 * x ** S("5/2"))

    assert tn_branch(expint, 1)
    assert tn_branch(expint, 2)
    assert tn_branch(expint, 3)
    assert tn_branch(expint, 1.7)
    assert tn_branch(expint, pi)

    assert expint(y, x * exp_polar(2 * I * pi)) == x ** (y - 1) * (exp(2 * I * pi * y) - 1) * gamma(-y + 1) + expint(
        y, x
    )
    assert expint(y, x * exp_polar(-2 * I * pi)) == x ** (y - 1) * (exp(-2 * I * pi * y) - 1) * gamma(-y + 1) + expint(
        y, x
    )
    assert expint(2, x * exp_polar(2 * I * pi)) == 2 * I * pi * x + expint(2, x)
    assert expint(2, x * exp_polar(-2 * I * pi)) == -2 * I * pi * x + expint(2, x)
    assert expint(1, x).rewrite(Ei).rewrite(expint) == expint(1, x)

    assert mytn(E1(x), E1(x).rewrite(Shi), Shi(x) - Chi(x), x)
    assert mytn(E1(polar_lift(I) * x), E1(polar_lift(I) * x).rewrite(Si), -Ci(x) + I * Si(x) - I * pi / 2, x)

    assert mytn(expint(2, x), expint(2, x).rewrite(Ei).rewrite(expint), -x * E1(x) + exp(-x), x)
    assert mytn(expint(3, x), expint(3, x).rewrite(Ei).rewrite(expint), x ** 2 * E1(x) / 2 + (1 - x) * exp(-x) / 2, x)
示例#27
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def test_meijerg_formulae():
    from sympy.simplify.hyperexpand import MeijerFormulaCollection
    formulae = MeijerFormulaCollection().formulae
    for sig in formulae:
        for formula in formulae[sig]:
            g = meijerg(formula.func.an, formula.func.ap,
                        formula.func.bm, formula.func.bq,
                        formula.z)
            rep = {}
            for sym in formula.symbols:
                rep[sym] = randcplx()

            # first test if the closed-form is actually correct
            g = g.subs(rep)
            closed_form = formula.closed_form.subs(rep)
            z = formula.z
            assert tn(g, closed_form, z)

            # now test the computed matrix
            cl = (formula.C * formula.B)[0].subs(rep)
            assert tn(closed_form, cl, z)
            deriv1 = z*formula.B.diff(z)
            deriv2 = formula.M * formula.B
            for d1, d2 in zip(deriv1, deriv2):
                assert tn(d1.subs(rep), d2.subs(rep), z)
示例#28
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def test_lerchphi():
    from sympy import combsimp, exp_polar, polylog, log, lerchphi
    assert hyperexpand(hyper([1, a], [a + 1], z)/a) == lerchphi(z, 1, a)
    assert hyperexpand(
        hyper([1, a, a], [a + 1, a + 1], z)/a**2) == lerchphi(z, 2, a)
    assert hyperexpand(hyper([1, a, a, a], [a + 1, a + 1, a + 1], z)/a**3) == \
           lerchphi(z, 3, a)
    assert hyperexpand(hyper([1] + [a]*10, [a + 1]*10, z)/a**10) \
           == lerchphi(z, 10, a)
    assert combsimp(hyperexpand(meijerg([0, 1 - a], [], [0], [-a],
                    exp_polar(-I*pi)*z))) == \
           lerchphi(z, 1, a)
    assert combsimp(hyperexpand(meijerg([0, 1 - a, 1 - a], [], [0], [-a, -a],
                    exp_polar(-I*pi)*z))) == \
           lerchphi(z, 2, a)
    assert combsimp(
        hyperexpand(meijerg([0, 1 - a, 1 - a, 1 - a], [], [0], [-a, -a, -a],
                    exp_polar(-I*pi)*z))) == \
           lerchphi(z, 3, a)

    assert hyperexpand(z*hyper([1, 1], [2], z)) == -log(1 + -z)
    assert hyperexpand(z*hyper([1, 1, 1], [2, 2], z)) == polylog(2, z)
    assert hyperexpand(z*hyper([1, 1, 1, 1], [2, 2, 2], z)) == polylog(3, z)

    assert hyperexpand(hyper([1, a, 1 + S(1)/2], [a + 1, S(1)/2], z)) == \
           -2*a/(z - 1) + (-2*a**2 + a)*lerchphi(z, 1, a)

    # Now numerical tests. These make sure reductions etc are carried out
    # correctly

    # a rational function (polylog at negative integer order)
    assert can_do([2, 2, 2], [1, 1])

    # NOTE these contain log(1-x) etc ... better make sure we have |z| < 1
    # reduction of order for polylog
    assert can_do([1, 1, 1, b + 5], [2, 2, b], div=10)

    # reduction of order for lerchphi
    # XXX lerchphi in mpmath is flaky
    assert can_do(
        [1, a, a, a, b + 5], [a + 1, a + 1, a + 1, b], numerical=False)

    # test a bug
    from sympy import Abs
    assert hyperexpand(hyper([S(1)/2, S(1)/2, S(1)/2, 1],
                             [S(3)/2, S(3)/2, S(3)/2], S(1)/4)) == \
        Abs(-polylog(3, exp_polar(I*pi)/2) + polylog(3, S(1)/2))
示例#29
0
 def fdiff(self, argindex):
     from sympy import meijerg
     nu, z = self.args
     if argindex == 1:
         return -z**(nu - 1)*meijerg([], [1, 1], [0, 0, 1 - nu], [], z)
     elif argindex == 2:
         return -expint(nu - 1, z)
     else:
         raise ArgumentIndexError(self, argindex)
示例#30
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 def fdiff(self, argindex=2):
     from sympy import meijerg
     if argindex == 2:
         a, z = self.args
         return -C.exp(-z)*z**(a-1)
     elif argindex == 1:
         a, z = self.args
         return uppergamma(a, z)*log(z) + meijerg([], [1, 1], [0, 0, a], [], z)
     else:
         raise ArgumentIndexError(self, argindex)
示例#31
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def test_limits():
    k, x = symbols('k, x')
    assert hyper((1,), (Rational(4, 3), Rational(5, 3)), k**2).series(k) == \
           1 + 9*k**2/20 + 81*k**4/1120 + O(k**6) # issue 6350
    assert limit(meijerg((), (), (1,), (0,), -x), x, 0) == \
            meijerg(((), ()), ((1,), (0,)), 0) # issue 6052
示例#32
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def test_erf():
    assert erf(nan) is nan

    assert erf(oo) == 1
    assert erf(-oo) == -1

    assert erf(0) == 0

    assert erf(I * oo) == oo * I
    assert erf(-I * oo) == -oo * I

    assert erf(-2) == -erf(2)
    assert erf(-x * y) == -erf(x * y)
    assert erf(-x - y) == -erf(x + y)

    assert erf(erfinv(x)) == x
    assert erf(erfcinv(x)) == 1 - x
    assert erf(erf2inv(0, x)) == x
    assert erf(erf2inv(0, x, evaluate=False)) == x  # To cover code in erf
    assert erf(erf2inv(0, erf(erfcinv(1 - erf(erfinv(x)))))) == x

    assert erf(I).is_real == False
    assert erf(0).is_real == True

    assert conjugate(erf(z)) == erf(conjugate(z))

    assert erf(x).as_leading_term(x) == 2 * x / sqrt(pi)
    assert erf(x * y).as_leading_term(y) == 2 * x * y / sqrt(pi)
    assert (erf(x * y) / erf(y)).as_leading_term(y) == x
    assert erf(1 / x).as_leading_term(x) == erf(1 / x)

    assert erf(z).rewrite('uppergamma') == sqrt(z**
                                                2) * (1 - erfc(sqrt(z**2))) / z
    assert erf(z).rewrite('erfc') == S.One - erfc(z)
    assert erf(z).rewrite('erfi') == -I * erfi(I * z)
    assert erf(z).rewrite('fresnels') == (1 + I) * (
        fresnelc(z * (1 - I) / sqrt(pi)) - I * fresnels(z *
                                                        (1 - I) / sqrt(pi)))
    assert erf(z).rewrite('fresnelc') == (1 + I) * (
        fresnelc(z * (1 - I) / sqrt(pi)) - I * fresnels(z *
                                                        (1 - I) / sqrt(pi)))
    assert erf(z).rewrite('hyper') == 2 * z * hyper([S.Half], [3 * S.Half],
                                                    -z**2) / sqrt(pi)
    assert erf(z).rewrite('meijerg') == z * meijerg(
        [S.Half], [], [0], [Rational(-1, 2)], z**2) / sqrt(pi)
    assert erf(z).rewrite(
        'expint') == sqrt(z**2) / z - z * expint(S.Half, z**2) / sqrt(S.Pi)

    assert limit(exp(x)*exp(x**2)*(erf(x + 1/exp(x)) - erf(x)), x, oo) == \
        2/sqrt(pi)
    assert limit((1 - erf(z)) * exp(z**2) * z, z, oo) == 1 / sqrt(pi)
    assert limit((1 - erf(x)) * exp(x**2) * sqrt(pi) * x, x, oo) == 1
    assert limit(((1 - erf(x)) * exp(x**2) * sqrt(pi) * x - 1) * 2 * x**2, x,
                 oo) == -1
    assert limit(erf(x) / x, x, 0) == 2 / sqrt(pi)
    assert limit(x**(-4) - sqrt(pi) * erf(x**2) / (2 * x**6), x, 0) == S(1) / 3

    assert erf(x).as_real_imag() == \
        (erf(re(x) - I*im(x))/2 + erf(re(x) + I*im(x))/2,
         -I*(-erf(re(x) - I*im(x)) + erf(re(x) + I*im(x)))/2)

    assert erf(x).as_real_imag(deep=False) == \
        (erf(re(x) - I*im(x))/2 + erf(re(x) + I*im(x))/2,
         -I*(-erf(re(x) - I*im(x)) + erf(re(x) + I*im(x)))/2)

    assert erf(w).as_real_imag() == (erf(w), 0)
    assert erf(w).as_real_imag(deep=False) == (erf(w), 0)
    # issue 13575
    assert erf(I).as_real_imag() == (0, -I * erf(I))

    raises(ArgumentIndexError, lambda: erf(x).fdiff(2))

    assert erf(x).inverse() == erfinv
示例#33
0
def test_meijer():
    raises(TypeError, lambda: meijerg(1, z))
    raises(TypeError, lambda: meijerg(((1,), (2,)), (3,), (4,), z))

    assert meijerg(((1, 2), (3,)), ((4,), (5,)), z) == meijerg(
        Tuple(1, 2), Tuple(3), Tuple(4), Tuple(5), z
    )

    g = meijerg((1, 2), (3, 4, 5), (6, 7, 8, 9), (10, 11, 12, 13, 14), z)
    assert g.an == Tuple(1, 2)
    assert g.ap == Tuple(1, 2, 3, 4, 5)
    assert g.aother == Tuple(3, 4, 5)
    assert g.bm == Tuple(6, 7, 8, 9)
    assert g.bq == Tuple(6, 7, 8, 9, 10, 11, 12, 13, 14)
    assert g.bother == Tuple(10, 11, 12, 13, 14)
    assert g.argument == z
    assert g.nu == 75
    assert g.delta == -1
    assert g.is_commutative is True
    assert g.is_number is False
    # issue 13071
    assert meijerg([[], []], [[S.Half], [0]], 1).is_number is True

    assert meijerg([1, 2], [3], [4], [5], z).delta == S.Half

    # just a few checks to make sure that all arguments go where they should
    assert tn(meijerg(Tuple(), Tuple(), Tuple(0), Tuple(), -z), exp(z), z)
    assert tn(
        sqrt(pi) * meijerg(Tuple(), Tuple(), Tuple(0), Tuple(S.Half), z ** 2 / 4),
        cos(z),
        z,
    )
    assert tn(meijerg(Tuple(1, 1), Tuple(), Tuple(1), Tuple(0), z), log(1 + z), z)

    # test exceptions
    raises(ValueError, lambda: meijerg(((3, 1), (2,)), ((oo,), (2, 0)), x))
    raises(ValueError, lambda: meijerg(((3, 1), (2,)), ((1,), (2, 0)), x))

    # differentiation
    g = meijerg(
        (randcplx(),), (randcplx() + 2 * I,), Tuple(), (randcplx(), randcplx()), z
    )
    assert td(g, z)

    g = meijerg(Tuple(), (randcplx(),), Tuple(), (randcplx(), randcplx()), z)
    assert td(g, z)

    g = meijerg(Tuple(), Tuple(), Tuple(randcplx()), Tuple(randcplx(), randcplx()), z)
    assert td(g, z)

    a1, a2, b1, b2, c1, c2, d1, d2 = symbols("a1:3, b1:3, c1:3, d1:3")
    assert (
        meijerg((a1, a2), (b1, b2), (c1, c2), (d1, d2), z).diff(z)
        == (
            meijerg((a1 - 1, a2), (b1, b2), (c1, c2), (d1, d2), z)
            + (a1 - 1) * meijerg((a1, a2), (b1, b2), (c1, c2), (d1, d2), z)
        )
        / z
    )

    assert meijerg([z, z], [], [], [], z).diff(z) == Derivative(
        meijerg([z, z], [], [], [], z), z
    )

    # meijerg is unbranched wrt parameters
    from sympy import polar_lift as pl

    assert meijerg([pl(a1)], [pl(a2)], [pl(b1)], [pl(b2)], pl(z)) == meijerg(
        [a1], [a2], [b1], [b2], pl(z)
    )

    # integrand
    from sympy.abc import a, b, c, d, s

    assert meijerg([a], [b], [c], [d], z).integrand(s) == z ** s * gamma(c - s) * gamma(
        -a + s + 1
    ) / (gamma(b - s) * gamma(-d + s + 1))
示例#34
0
def test_fresnel():
    assert fresnels(0) == 0
    assert fresnels(oo) == S.Half
    assert fresnels(-oo) == Rational(-1, 2)
    assert fresnels(I * oo) == -I * S.Half

    assert unchanged(fresnels, z)
    assert fresnels(-z) == -fresnels(z)
    assert fresnels(I * z) == -I * fresnels(z)
    assert fresnels(-I * z) == I * fresnels(z)

    assert conjugate(fresnels(z)) == fresnels(conjugate(z))

    assert fresnels(z).diff(z) == sin(pi * z**2 / 2)

    assert fresnels(z).rewrite(erf) == (S.One + I) / 4 * (erf(
        (S.One + I) / 2 * sqrt(pi) * z) - I * erf(
            (S.One - I) / 2 * sqrt(pi) * z))

    assert fresnels(z).rewrite(hyper) == \
        pi*z**3/6 * hyper([Rational(3, 4)], [Rational(3, 2), Rational(7, 4)], -pi**2*z**4/16)

    assert fresnels(z).series(z, n=15) == \
        pi*z**3/6 - pi**3*z**7/336 + pi**5*z**11/42240 + O(z**15)

    assert fresnels(w).is_extended_real == True
    assert fresnels(w).is_finite == True

    assert fresnels(z).is_extended_real is None
    assert fresnels(z).is_finite is None

    assert fresnels(z).as_real_imag() == (
        fresnels(re(z) - I * im(z)) / 2 + fresnels(re(z) + I * im(z)) / 2,
        -I * (-fresnels(re(z) - I * im(z)) + fresnels(re(z) + I * im(z))) / 2)

    assert fresnels(z).as_real_imag(deep=False) == (
        fresnels(re(z) - I * im(z)) / 2 + fresnels(re(z) + I * im(z)) / 2,
        -I * (-fresnels(re(z) - I * im(z)) + fresnels(re(z) + I * im(z))) / 2)

    assert fresnels(w).as_real_imag() == (fresnels(w), 0)
    assert fresnels(w).as_real_imag(deep=True) == (fresnels(w), 0)

    assert fresnels(2 + 3 * I).as_real_imag() == (
        fresnels(2 + 3 * I) / 2 + fresnels(2 - 3 * I) / 2,
        -I * (fresnels(2 + 3 * I) - fresnels(2 - 3 * I)) / 2)

    assert expand_func(integrate(fresnels(z), z)) == \
        z*fresnels(z) + cos(pi*z**2/2)/pi

    assert fresnels(z).rewrite(meijerg) == sqrt(2)*pi*z**Rational(9, 4) * \
        meijerg(((), (1,)), ((Rational(3, 4),),
        (Rational(1, 4), 0)), -pi**2*z**4/16)/(2*(-z)**Rational(3, 4)*(z**2)**Rational(3, 4))

    assert fresnelc(0) == 0
    assert fresnelc(oo) == S.Half
    assert fresnelc(-oo) == Rational(-1, 2)
    assert fresnelc(I * oo) == I * S.Half

    assert unchanged(fresnelc, z)
    assert fresnelc(-z) == -fresnelc(z)
    assert fresnelc(I * z) == I * fresnelc(z)
    assert fresnelc(-I * z) == -I * fresnelc(z)

    assert conjugate(fresnelc(z)) == fresnelc(conjugate(z))

    assert fresnelc(z).diff(z) == cos(pi * z**2 / 2)

    assert fresnelc(z).rewrite(erf) == (S.One - I) / 4 * (erf(
        (S.One + I) / 2 * sqrt(pi) * z) + I * erf(
            (S.One - I) / 2 * sqrt(pi) * z))

    assert fresnelc(z).rewrite(hyper) == \
        z * hyper([Rational(1, 4)], [S.Half, Rational(5, 4)], -pi**2*z**4/16)

    assert fresnelc(w).is_extended_real == True

    assert fresnelc(z).as_real_imag() == \
        (fresnelc(re(z) - I*im(z))/2 + fresnelc(re(z) + I*im(z))/2,
         -I*(-fresnelc(re(z) - I*im(z)) + fresnelc(re(z) + I*im(z)))/2)

    assert fresnelc(z).as_real_imag(deep=False) == \
        (fresnelc(re(z) - I*im(z))/2 + fresnelc(re(z) + I*im(z))/2,
         -I*(-fresnelc(re(z) - I*im(z)) + fresnelc(re(z) + I*im(z)))/2)

    assert fresnelc(2 + 3 * I).as_real_imag() == (
        fresnelc(2 - 3 * I) / 2 + fresnelc(2 + 3 * I) / 2,
        -I * (fresnelc(2 + 3 * I) - fresnelc(2 - 3 * I)) / 2)

    assert expand_func(integrate(fresnelc(z), z)) == \
        z*fresnelc(z) - sin(pi*z**2/2)/pi

    assert fresnelc(z).rewrite(meijerg) == sqrt(2)*pi*z**Rational(3, 4) * \
        meijerg(((), (1,)), ((Rational(1, 4),),
        (Rational(3, 4), 0)), -pi**2*z**4/16)/(2*(-z)**Rational(1, 4)*(z**2)**Rational(1, 4))

    from sympy.testing.randtest import verify_numerically

    verify_numerically(re(fresnels(z)), fresnels(z).as_real_imag()[0], z)
    verify_numerically(im(fresnels(z)), fresnels(z).as_real_imag()[1], z)
    verify_numerically(fresnels(z), fresnels(z).rewrite(hyper), z)
    verify_numerically(fresnels(z), fresnels(z).rewrite(meijerg), z)

    verify_numerically(re(fresnelc(z)), fresnelc(z).as_real_imag()[0], z)
    verify_numerically(im(fresnelc(z)), fresnelc(z).as_real_imag()[1], z)
    verify_numerically(fresnelc(z), fresnelc(z).rewrite(hyper), z)
    verify_numerically(fresnelc(z), fresnelc(z).rewrite(meijerg), z)

    raises(ArgumentIndexError, lambda: fresnels(z).fdiff(2))
    raises(ArgumentIndexError, lambda: fresnelc(z).fdiff(2))

    assert fresnels(x).taylor_term(-1, x) is S.Zero
    assert fresnelc(x).taylor_term(-1, x) is S.Zero
    assert fresnelc(x).taylor_term(1, x) == -pi**2 * x**5 / 40
示例#35
0
def test_expint():
    assert mytn(expint(x, y),
                expint(x, y).rewrite(uppergamma),
                y**(x - 1) * uppergamma(1 - x, y), x)
    assert mytd(expint(x, y),
                -y**(x - 1) * meijerg([], [1, 1], [0, 0, 1 - x], [], y), x)
    assert mytd(expint(x, y), -expint(x - 1, y), y)
    assert mytn(expint(1, x),
                expint(1, x).rewrite(Ei), -Ei(x * polar_lift(-1)) + I * pi, x)

    assert expint(-4, x) == exp(-x)/x + 4*exp(-x)/x**2 + 12*exp(-x)/x**3 \
        + 24*exp(-x)/x**4 + 24*exp(-x)/x**5
    assert expint(Rational(-3, 2), x) == \
        exp(-x)/x + 3*exp(-x)/(2*x**2) + 3*sqrt(pi)*erfc(sqrt(x))/(4*x**S('5/2'))

    assert tn_branch(expint, 1)
    assert tn_branch(expint, 2)
    assert tn_branch(expint, 3)
    assert tn_branch(expint, 1.7)
    assert tn_branch(expint, pi)

    assert expint(y, x*exp_polar(2*I*pi)) == \
        x**(y - 1)*(exp(2*I*pi*y) - 1)*gamma(-y + 1) + expint(y, x)
    assert expint(y, x*exp_polar(-2*I*pi)) == \
        x**(y - 1)*(exp(-2*I*pi*y) - 1)*gamma(-y + 1) + expint(y, x)
    assert expint(2,
                  x * exp_polar(2 * I * pi)) == 2 * I * pi * x + expint(2, x)
    assert expint(2, x *
                  exp_polar(-2 * I * pi)) == -2 * I * pi * x + expint(2, x)
    assert expint(1, x).rewrite(Ei).rewrite(expint) == expint(1, x)
    assert expint(x, y).rewrite(Ei) == expint(x, y)
    assert expint(x, y).rewrite(Ci) == expint(x, y)

    assert mytn(E1(x), E1(x).rewrite(Shi), Shi(x) - Chi(x), x)
    assert mytn(E1(polar_lift(I) * x),
                E1(polar_lift(I) * x).rewrite(Si),
                -Ci(x) + I * Si(x) - I * pi / 2, x)

    assert mytn(expint(2, x),
                expint(2, x).rewrite(Ei).rewrite(expint), -x * E1(x) + exp(-x),
                x)
    assert mytn(expint(3, x),
                expint(3, x).rewrite(Ei).rewrite(expint),
                x**2 * E1(x) / 2 + (1 - x) * exp(-x) / 2, x)

    assert expint(Rational(3, 2), z).nseries(z) == \
        2 + 2*z - z**2/3 + z**3/15 - z**4/84 + z**5/540 - \
        2*sqrt(pi)*sqrt(z) + O(z**6)

    assert E1(z).series(z) == -EulerGamma - log(z) + z - \
        z**2/4 + z**3/18 - z**4/96 + z**5/600 + O(z**6)

    assert expint(4, z).series(z) == Rational(1, 3) - z/2 + z**2/2 + \
        z**3*(log(z)/6 - Rational(11, 36) + EulerGamma/6 - I*pi/6) - z**4/24 + \
        z**5/240 + O(z**6)
    assert expint(z, y).series(z, 0, 2) == exp(-y) / y - z * meijerg(
        ((), (1, 1)), ((0, 0, 1), ()), y) / y + O(z**2)
    raises(ArgumentIndexError, lambda: expint(x, y).fdiff(3))

    neg = Symbol('neg', negative=True)
    assert Ei(neg).rewrite(Si) == Shi(neg) + Chi(neg) - I * pi
示例#36
0
def plot_and_save(name):
    tmp_file = TmpFileManager.tmp_file

    x = Symbol('x')
    y = Symbol('y')
    z = Symbol('z')

    ###
    # Examples from the 'introduction' notebook
    ###

    p = plot(x)
    p = plot(x * sin(x), x * cos(x))
    p.extend(p)
    p[0].line_color = lambda a: a
    p[1].line_color = 'b'
    p.title = 'Big title'
    p.xlabel = 'the x axis'
    p[1].label = 'straight line'
    p.legend = True
    p.aspect_ratio = (1, 1)
    p.xlim = (-15, 20)
    p.save(tmp_file('%s_basic_options_and_colors' % name))
    p._backend.close()

    p.extend(plot(x + 1))
    p.append(plot(x + 3, x**2)[1])
    p.save(tmp_file('%s_plot_extend_append' % name))

    p[2] = plot(x**2, (x, -2, 3))
    p.save(tmp_file('%s_plot_setitem' % name))
    p._backend.close()

    p = plot(sin(x), (x, -2 * pi, 4 * pi))
    p.save(tmp_file('%s_line_explicit' % name))
    p._backend.close()

    p = plot(sin(x))
    p.save(tmp_file('%s_line_default_range' % name))
    p._backend.close()

    p = plot((x**2, (x, -5, 5)), (x**3, (x, -3, 3)))
    p.save(tmp_file('%s_line_multiple_range' % name))
    p._backend.close()

    raises(ValueError, lambda: plot(x, y))

    p = plot(Piecewise((1, x > 0), (0, True)), (x, -1, 1))
    p.save(tmp_file('%s_plot_piecewise' % name))
    p._backend.close()

    #parametric 2d plots.
    #Single plot with default range.
    plot_parametric(sin(x), cos(x)).save(tmp_file())

    #Single plot with range.
    p = plot_parametric(sin(x), cos(x), (x, -5, 5))
    p.save(tmp_file('%s_parametric_range' % name))
    p._backend.close()

    #Multiple plots with same range.
    p = plot_parametric((sin(x), cos(x)), (x, sin(x)))
    p.save(tmp_file('%s_parametric_multiple' % name))
    p._backend.close()

    #Multiple plots with different ranges.
    p = plot_parametric((sin(x), cos(x), (x, -3, 3)), (x, sin(x), (x, -5, 5)))
    p.save(tmp_file('%s_parametric_multiple_ranges' % name))
    p._backend.close()

    #depth of recursion specified.
    p = plot_parametric(x, sin(x), depth=13)
    p.save(tmp_file('%s_recursion_depth' % name))
    p._backend.close()

    #No adaptive sampling.
    p = plot_parametric(cos(x), sin(x), adaptive=False, nb_of_points=500)
    p.save(tmp_file('%s_adaptive' % name))
    p._backend.close()

    #3d parametric plots
    p = plot3d_parametric_line(sin(x), cos(x), x)
    p.save(tmp_file('%s_3d_line' % name))
    p._backend.close()

    p = plot3d_parametric_line((sin(x), cos(x), x, (x, -5, 5)),
                               (cos(x), sin(x), x, (x, -3, 3)))
    p.save(tmp_file('%s_3d_line_multiple' % name))
    p._backend.close()

    p = plot3d_parametric_line(sin(x), cos(x), x, nb_of_points=30)
    p.save(tmp_file('%s_3d_line_points' % name))
    p._backend.close()

    # 3d surface single plot.
    p = plot3d(x * y)
    p.save(tmp_file('%s_surface' % name))
    p._backend.close()

    # Multiple 3D plots with same range.
    p = plot3d(-x * y, x * y, (x, -5, 5))
    p.save(tmp_file('%s_surface_multiple' % name))
    p._backend.close()

    # Multiple 3D plots with different ranges.
    p = plot3d((x * y, (x, -3, 3), (y, -3, 3)),
               (-x * y, (x, -3, 3), (y, -3, 3)))
    p.save(tmp_file('%s_surface_multiple_ranges' % name))
    p._backend.close()

    # Single Parametric 3D plot
    p = plot3d_parametric_surface(sin(x + y), cos(x - y), x - y)
    p.save(tmp_file('%s_parametric_surface' % name))
    p._backend.close()

    # Multiple Parametric 3D plots.
    p = plot3d_parametric_surface(
        (x * sin(z), x * cos(z), z, (x, -5, 5), (z, -5, 5)),
        (sin(x + y), cos(x - y), x - y, (x, -5, 5), (y, -5, 5)))
    p.save(tmp_file('%s_parametric_surface' % name))
    p._backend.close()

    ###
    # Examples from the 'colors' notebook
    ###

    p = plot(sin(x))
    p[0].line_color = lambda a: a
    p.save(tmp_file('%s_colors_line_arity1' % name))

    p[0].line_color = lambda a, b: b
    p.save(tmp_file('%s_colors_line_arity2' % name))
    p._backend.close()

    p = plot(x * sin(x), x * cos(x), (x, 0, 10))
    p[0].line_color = lambda a: a
    p.save(tmp_file('%s_colors_param_line_arity1' % name))

    p[0].line_color = lambda a, b: a
    p.save(tmp_file('%s_colors_param_line_arity2a' % name))

    p[0].line_color = lambda a, b: b
    p.save(tmp_file('%s_colors_param_line_arity2b' % name))
    p._backend.close()

    p = plot3d_parametric_line(
        sin(x) + 0.1 * sin(x) * cos(7 * x),
        cos(x) + 0.1 * cos(x) * cos(7 * x), 0.1 * sin(7 * x), (x, 0, 2 * pi))
    p[0].line_color = lambdify_(x, sin(4 * x))
    p.save(tmp_file('%s_colors_3d_line_arity1' % name))
    p[0].line_color = lambda a, b: b
    p.save(tmp_file('%s_colors_3d_line_arity2' % name))
    p[0].line_color = lambda a, b, c: c
    p.save(tmp_file('%s_colors_3d_line_arity3' % name))
    p._backend.close()

    p = plot3d(sin(x) * y, (x, 0, 6 * pi), (y, -5, 5))
    p[0].surface_color = lambda a: a
    p.save(tmp_file('%s_colors_surface_arity1' % name))
    p[0].surface_color = lambda a, b: b
    p.save(tmp_file('%s_colors_surface_arity2' % name))
    p[0].surface_color = lambda a, b, c: c
    p.save(tmp_file('%s_colors_surface_arity3a' % name))
    p[0].surface_color = lambdify_((x, y, z), sqrt((x - 3 * pi)**2 + y**2))
    p.save(tmp_file('%s_colors_surface_arity3b' % name))
    p._backend.close()

    p = plot3d_parametric_surface(x * cos(4 * y), x * sin(4 * y), y,
                                  (x, -1, 1), (y, -1, 1))
    p[0].surface_color = lambda a: a
    p.save(tmp_file('%s_colors_param_surf_arity1' % name))
    p[0].surface_color = lambda a, b: a * b
    p.save(tmp_file('%s_colors_param_surf_arity2' % name))
    p[0].surface_color = lambdify_((x, y, z), sqrt(x**2 + y**2 + z**2))
    p.save(tmp_file('%s_colors_param_surf_arity3' % name))
    p._backend.close()

    ###
    # Examples from the 'advanced' notebook
    ###

    # XXX: This raises the warning "The evaluation of the expression is
    # problematic. We are trying a failback method that may still work. Please
    # report this as a bug." It has to use the fallback because using evalf()
    # is the only way to evaluate the integral. We should perhaps just remove
    # that warning.

    with warnings.catch_warnings(record=True) as w:
        i = Integral(log((sin(x)**2 + 1) * sqrt(x**2 + 1)), (x, 0, y))
        p = plot(i, (y, 1, 5))
        p.save(tmp_file('%s_advanced_integral' % name))
        p._backend.close()
        # Make sure no other warnings were raised
        assert len(w) == 1
        assert issubclass(w[-1].category, UserWarning)
        assert "The evaluation of the expression is problematic" in str(
            w[0].message)

    s = Sum(1 / x**y, (x, 1, oo))
    p = plot(s, (y, 2, 10))
    p.save(tmp_file('%s_advanced_inf_sum' % name))
    p._backend.close()

    p = plot(Sum(1 / x, (x, 1, y)), (y, 2, 10), show=False)
    p[0].only_integers = True
    p[0].steps = True
    p.save(tmp_file('%s_advanced_fin_sum' % name))
    p._backend.close()

    ###
    # Test expressions that can not be translated to np and generate complex
    # results.
    ###
    plot(sin(x) + I * cos(x)).save(tmp_file())
    plot(sqrt(sqrt(-x))).save(tmp_file())
    plot(LambertW(x)).save(tmp_file())
    plot(sqrt(LambertW(x))).save(tmp_file())

    #Characteristic function of a StudentT distribution with nu=10
    plot((meijerg(
        ((1 / 2, ), ()),
        ((5, 0, 1 / 2), ()), 5 * x**2 * exp_polar(-I * pi) / 2) + meijerg(
            ((1 / 2, ), ()),
            ((5, 0, 1 / 2),
             ()), 5 * x**2 * exp_polar(I * pi) / 2)) / (48 * pi),
         (x, 1e-6, 1e-2)).save(tmp_file())
示例#37
0
def test_meijerint():
    from sympy import symbols, expand, arg
    s, t, mu = symbols('s t mu', real=True)
    assert integrate(
        meijerg([], [], [0], [], s * t) *
        meijerg([], [], [mu / 2], [-mu / 2], t**2 / 4),
        (t, 0, oo)).is_Piecewise
    s = symbols('s', positive=True)
    assert integrate(x**s*meijerg([[],[]], [[0],[]], x), (x, 0, oo)) \
           == gamma(s + 1)
    assert integrate(x**s * meijerg([[], []], [[0], []], x), (x, 0, oo),
                     meijerg=True) == gamma(s + 1)
    assert isinstance(
        integrate(x**s * meijerg([[], []], [[0], []], x), (x, 0, oo),
                  meijerg=False), Integral)

    assert meijerint_indefinite(exp(x), x) == exp(x)

    # TODO what simplifications should be done automatically?
    # This tests "extra case" for antecedents_1.
    a, b = symbols('a b', positive=True)
    assert simplify(meijerint_definite(x**a, x, 0, b)[0]) \
           == b**(a + 1)/(a + 1)

    # This tests various conditions and expansions:
    meijerint_definite((x + 1)**3 * exp(-x), x, 0, oo) == (16, True)

    # Again, how about simplifications?
    sigma, mu = symbols('sigma mu', positive=True)
    i, c = meijerint_definite(exp(-((x - mu) / (2 * sigma))**2), x, 0, oo)
    assert simplify(i) \
           == sqrt(pi)*sigma*(erf(mu/(2*sigma)) + 1)
    assert c is True

    i, _ = meijerint_definite(exp(-mu * x) * exp(sigma * x), x, 0, oo)
    # TODO it would be nice to test the condition
    assert simplify(i) == 1 / (mu - sigma)

    # Test substitutions to change limits
    assert meijerint_definite(exp(x), x, -oo, 2) == (exp(2), True)
    assert expand(meijerint_definite(exp(x), x, 0, I)[0]) == exp(I) - 1
    assert expand(meijerint_definite(exp(-x), x, 0, x)[0]) == \
           1 - exp(-exp(I*arg(x))*abs(x))

    # Test -oo to oo
    assert meijerint_definite(exp(-x**2), x, -oo, oo) == (sqrt(pi), True)
    assert meijerint_definite(exp(-abs(x)), x, -oo, oo) == (2, True)
    assert meijerint_definite(exp(-(2 * x - 3)**2), x, -oo,
                              oo) == (sqrt(pi) / 2, True)
    assert meijerint_definite(exp(-abs(2 * x - 3)), x, -oo, oo) == (1, True)
    assert meijerint_definite(
        exp(-((x - mu) / sigma)**2 / 2) / sqrt(2 * pi * sigma**2), x, -oo,
        oo) == (1, True)

    # Test one of the extra conditions for 2 g-functinos
    assert meijerint_definite(exp(-x) * sin(x), x, 0, oo) == (S(1) / 2, True)

    # Test a bug
    def res(n):
        return (1 / (1 + x**2)).diff(x, n).subs(x, 1) * (-1)**n

    for n in range(6):
        assert integrate(exp(-x) * sin(x) * x**n, (x, 0, oo),
                         meijerg=True) == res(n)

    # Test trigexpand:
    assert integrate(exp(-x)*sin(x + a), (x, 0, oo), meijerg=True) == \
           sin(a)/2 + cos(a)/2
示例#38
0
def test_lowergamma():
    from sympy import meijerg, exp_polar, I, expint
    assert lowergamma(x, 0) == 0
    assert lowergamma(x, y).diff(y) == y**(x - 1) * exp(-y)
    assert td(lowergamma(randcplx(), y), y)
    assert td(lowergamma(x, randcplx()), x)
    assert lowergamma(x, y).diff(x) == \
        gamma(x)*digamma(x) - uppergamma(x, y)*log(y) \
        - meijerg([], [1, 1], [0, 0, x], [], y)

    assert lowergamma(S.Half, x) == sqrt(pi) * erf(sqrt(x))
    assert not lowergamma(S.Half - 3, x).has(lowergamma)
    assert not lowergamma(S.Half + 3, x).has(lowergamma)
    assert lowergamma(S.Half, x, evaluate=False).has(lowergamma)
    assert tn(lowergamma(S.Half + 3, x, evaluate=False),
              lowergamma(S.Half + 3, x), x)
    assert tn(lowergamma(S.Half - 3, x, evaluate=False),
              lowergamma(S.Half - 3, x), x)

    assert tn_branch(-3, lowergamma)
    assert tn_branch(-4, lowergamma)
    assert tn_branch(Rational(1, 3), lowergamma)
    assert tn_branch(pi, lowergamma)
    assert lowergamma(3, exp_polar(4 * pi * I) * x) == lowergamma(3, x)
    assert lowergamma(y, exp_polar(5*pi*I)*x) == \
        exp(4*I*pi*y)*lowergamma(y, x*exp_polar(pi*I))
    assert lowergamma(-2, exp_polar(5*pi*I)*x) == \
        lowergamma(-2, x*exp_polar(I*pi)) + 2*pi*I

    assert conjugate(lowergamma(x, y)) == lowergamma(conjugate(x),
                                                     conjugate(y))
    assert conjugate(lowergamma(x, 0)) == 0
    assert unchanged(conjugate, lowergamma(x, -oo))

    assert lowergamma(0, x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(S(1) / 3, x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(1, x, evaluate=False)._eval_is_meromorphic(x, 0) == True
    assert lowergamma(x, x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(x + 1, x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(1 / x, x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(0, x + 1)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(S(1) / 3, x + 1)._eval_is_meromorphic(x, 0) == True
    assert lowergamma(1, x + 1, evaluate=False)._eval_is_meromorphic(x,
                                                                     0) == True
    assert lowergamma(x, x + 1)._eval_is_meromorphic(x, 0) == True
    assert lowergamma(x + 1, x + 1)._eval_is_meromorphic(x, 0) == True
    assert lowergamma(1 / x, x + 1)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(0, 1 / x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(S(1) / 3, 1 / x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(1, 1 / x,
                      evaluate=False)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(x, 1 / x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(x + 1, 1 / x)._eval_is_meromorphic(x, 0) == False
    assert lowergamma(1 / x, 1 / x)._eval_is_meromorphic(x, 0) == False

    assert lowergamma(x, 2).series(x, oo, 3) == \
        2**x*(1 + 2/(x + 1))*exp(-2)/x + O(exp(x*log(2))/x**3, (x, oo))

    assert lowergamma(
        x, y).rewrite(expint) == -y**x * expint(-x + 1, y) + gamma(x)
    k = Symbol('k', integer=True)
    assert lowergamma(
        k, y).rewrite(expint) == -y**k * expint(-k + 1, y) + gamma(k)
    k = Symbol('k', integer=True, positive=False)
    assert lowergamma(k, y).rewrite(expint) == lowergamma(k, y)
    assert lowergamma(x, y).rewrite(uppergamma) == gamma(x) - uppergamma(x, y)

    assert lowergamma(70, 6) == factorial(
        69
    ) - 69035724522603011058660187038367026272747334489677105069435923032634389419656200387949342530805432320 * exp(
        -6)
    assert (lowergamma(S(77) / 2, 6) -
            lowergamma(S(77) / 2, 6, evaluate=False)).evalf() < 1e-16
    assert (lowergamma(-S(77) / 2, 6) -
            lowergamma(-S(77) / 2, 6, evaluate=False)).evalf() < 1e-16
示例#39
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def test_meijerg_expand():
    from sympy import combsimp, simplify
    # from mpmath docs
    assert hyperexpand(meijerg([[], []], [[0], []], -z)) == exp(z)

    assert hyperexpand(meijerg([[1,1],[]], [[1],[0]], z)) == \
        log(z + 1)
    assert hyperexpand(meijerg([[1,1],[]], [[1],[1]], z)) == \
        z/(z + 1)
    assert hyperexpand(meijerg([[],[]], [[S(1)/2],[0]], (z/2)**2)) \
           == sin(z)/sqrt(pi)
    assert hyperexpand(meijerg([[],[]], [[0], [S(1)/2]], (z/2)**2)) \
           == cos(z)/sqrt(pi)
    assert can_do_meijer([], [a], [a - 1, a - S.Half], [])
    assert can_do_meijer([], [], [a / 2], [-a / 2], False)  # branches...
    assert can_do_meijer([a], [b], [a], [b, a - 1])

    # wikipedia
    assert hyperexpand(meijerg([1], [], [], [0], z)) == \
       Piecewise((0, abs(z) < 1), (1, abs(1/z) < 1),
                 (meijerg([1], [], [], [0], z), True))
    assert hyperexpand(meijerg([], [1], [0], [], z)) == \
       Piecewise((1, abs(z) < 1), (0, abs(1/z) < 1),
                 (meijerg([], [1], [0], [], z), True))

    # The Special Functions and their Approximations
    assert can_do_meijer([], [], [a + b / 2], [a, a - b / 2, a + S.Half])
    assert can_do_meijer([], [], [a], [b],
                         False)  # branches only agree for small z
    assert can_do_meijer([], [S.Half], [a], [-a])
    assert can_do_meijer([], [], [a, b], [])
    assert can_do_meijer([], [], [a, b], [])
    assert can_do_meijer([], [], [a, a + S.Half], [b, b + S.Half])
    assert can_do_meijer([], [], [a, -a], [0, S.Half], False)  # dito
    assert can_do_meijer([], [], [a, a + S.Half, b, b + S.Half], [])
    assert can_do_meijer([S.Half], [], [0], [a, -a])
    assert can_do_meijer([S.Half], [], [a], [0, -a], False)  # dito
    assert can_do_meijer([], [a - S.Half], [a, b], [a - S.Half], False)
    assert can_do_meijer([], [a + S.Half], [a + b, a - b, a], [], False)
    assert can_do_meijer([a + S.Half], [], [b, 2 * a - b, a], [], False)

    # This for example is actually zero.
    assert can_do_meijer([], [], [], [a, b])

    # Testing a bug:
    assert hyperexpand(meijerg([0, 2], [], [], [-1, 1], z)) == \
        Piecewise((0, abs(z) < 1),
                  (z*(1 - 1/z**2)/2, abs(1/z) < 1),
                  (meijerg([0, 2], [], [], [-1, 1], z), True))

    # Test that the simplest possible answer is returned:
    assert combsimp(simplify(hyperexpand(meijerg([1], [1-a], [-a/2, -a/2 + S(1)/2],
                                                 [], 1/z)))) == \
           -2*sqrt(pi)*(sqrt(z + 1) + 1)**a/a
示例#40
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 def tn(expr):
     assert _rewrite_single(meijerg([a], [b], [c], [d], expr), x) is None
示例#41
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 def t(expr, c, m):
     e = _rewrite_single(meijerg([a], [b], [c], [d], expr), x)
     assert e is not None
     assert isinstance(e[0][0][2], meijerg)
     assert e[0][0][2].argument.as_coeff_mul(x) == (c, (m, ))
示例#42
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def test_meijerg_derivative():
    assert meijerg([], [1, 1], [0, 0, x], [], z).diff(x) == log(z) * meijerg(
        [], [1, 1], [0, 0, x], [], z
    ) + 2 * meijerg([], [1, 1, 1], [0, 0, x, 0], [], z)

    y = randcplx()
    a = 5  # mpmath chokes with non-real numbers, and Mod1 with floats
    assert td(meijerg([x], [], [], [], y), x)
    assert td(meijerg([x ** 2], [], [], [], y), x)
    assert td(meijerg([], [x], [], [], y), x)
    assert td(meijerg([], [], [x], [], y), x)
    assert td(meijerg([], [], [], [x], y), x)
    assert td(meijerg([x], [a], [a + 1], [], y), x)
    assert td(meijerg([x], [a + 1], [a], [], y), x)
    assert td(meijerg([x, a], [], [], [a + 1], y), x)
    assert td(meijerg([x, a + 1], [], [], [a], y), x)
    b = Rational(3, 2)
    assert td(meijerg([a + 2], [b], [b - 3, x], [a], y), x)
示例#43
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def test_rewrite1():
    assert _rewrite1(x**3*meijerg([a], [b], [c], [d], x**2 + y*x**2)*5, x) == \
        (5, x**3, [(1, 0, meijerg([a], [b], [c], [d], x**2*(y + 1)))], True)
示例#44
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def test_branch_bug():
    assert hyperexpand(hyper((-S(1)/3, S(1)/2), (S(2)/3, S(3)/2), -z)) == \
           -z**S('1/3')*lowergamma(exp_polar(I*pi)/3, z)/5 \
           + sqrt(pi)*erf(sqrt(z))/(5*sqrt(z))
    assert hyperexpand(meijerg([S(7)/6, 1], [], [S(2)/3], [S(1)/6, 0], z)) == \
           2*z**S('2/3')*(2*sqrt(pi)*erf(sqrt(z))/sqrt(z) - 2*lowergamma(S(2)/3, z)/z**S('2/3'))*gamma(S(2)/3)/gamma(S(5)/3)
示例#45
0
def plot_and_save(name):

    tmp_file = TmpFileManager.tmp_file

    x = Symbol('x')
    y = Symbol('y')
    z = Symbol('z')

    ###
    # Examples from the 'introduction' notebook
    ###

    p = plot(x)
    p = plot(x * sin(x), x * cos(x))
    p.extend(p)
    p[0].line_color = lambda a: a
    p[1].line_color = 'b'
    p.title = 'Big title'
    p.xlabel = 'the x axis'
    p[1].label = 'straight line'
    p.legend = True
    p.aspect_ratio = (1, 1)
    p.xlim = (-15, 20)
    p.save(tmp_file('%s_basic_options_and_colors' % name))

    p.extend(plot(x + 1))
    p.append(plot(x + 3, x**2)[1])
    p.save(tmp_file('%s_plot_extend_append' % name))

    p[2] = plot(x**2, (x, -2, 3))
    p.save(tmp_file('%s_plot_setitem' % name))

    p = plot(sin(x), (x, -2 * pi, 4 * pi))
    p.save(tmp_file('%s_line_explicit' % name))

    p = plot(sin(x))
    p.save(tmp_file('%s_line_default_range' % name))

    p = plot((x**2, (x, -5, 5)), (x**3, (x, -3, 3)))
    p.save(tmp_file('%s_line_multiple_range' % name))

    raises(ValueError, lambda: plot(x, y))

    #parametric 2d plots.
    #Single plot with default range.
    plot_parametric(sin(x), cos(x)).save(tmp_file())

    #Single plot with range.
    p = plot_parametric(sin(x), cos(x), (x, -5, 5))
    p.save(tmp_file('%s_parametric_range' % name))

    #Multiple plots with same range.
    p = plot_parametric((sin(x), cos(x)), (x, sin(x)))
    p.save(tmp_file('%s_parametric_multiple' % name))

    #Multiple plots with different ranges.
    p = plot_parametric((sin(x), cos(x), (x, -3, 3)), (x, sin(x), (x, -5, 5)))
    p.save(tmp_file('%s_parametric_multiple_ranges' % name))

    #depth of recursion specified.
    p = plot_parametric(x, sin(x), depth=13)
    p.save(tmp_file('%s_recursion_depth' % name))

    #No adaptive sampling.
    p = plot_parametric(cos(x), sin(x), adaptive=False, nb_of_points=500)
    p.save(tmp_file('%s_adaptive' % name))

    #3d parametric plots
    p = plot3d_parametric_line(sin(x), cos(x), x)
    p.save(tmp_file('%s_3d_line' % name))

    p = plot3d_parametric_line((sin(x), cos(x), x, (x, -5, 5)),
                               (cos(x), sin(x), x, (x, -3, 3)))
    p.save(tmp_file('%s_3d_line_multiple' % name))

    p = plot3d_parametric_line(sin(x), cos(x), x, nb_of_points=30)
    p.save(tmp_file('%s_3d_line_points' % name))

    # 3d surface single plot.
    p = plot3d(x * y)
    p.save(tmp_file('%s_surface' % name))

    # Multiple 3D plots with same range.
    p = plot3d(-x * y, x * y, (x, -5, 5))
    p.save(tmp_file('%s_surface_multiple' % name))

    # Multiple 3D plots with different ranges.
    p = plot3d((x * y, (x, -3, 3), (y, -3, 3)),
               (-x * y, (x, -3, 3), (y, -3, 3)))
    p.save(tmp_file('%s_surface_multiple_ranges' % name))

    # Single Parametric 3D plot
    p = plot3d_parametric_surface(sin(x + y), cos(x - y), x - y)
    p.save(tmp_file('%s_parametric_surface' % name))

    # Multiple Parametric 3D plots.
    p = plot3d_parametric_surface(
        (x * sin(z), x * cos(z), z, (x, -5, 5), (z, -5, 5)),
        (sin(x + y), cos(x - y), x - y, (x, -5, 5), (y, -5, 5)))
    p.save(tmp_file('%s_parametric_surface' % name))

    ###
    # Examples from the 'colors' notebook
    ###

    p = plot(sin(x))
    p[0].line_color = lambda a: a
    p.save(tmp_file('%s_colors_line_arity1' % name))

    p[0].line_color = lambda a, b: b
    p.save(tmp_file('%s_colors_line_arity2' % name))

    p = plot(x * sin(x), x * cos(x), (x, 0, 10))
    p[0].line_color = lambda a: a
    p.save(tmp_file('%s_colors_param_line_arity1' % name))

    p[0].line_color = lambda a, b: a
    p.save(tmp_file('%s_colors_param_line_arity2a' % name))

    p[0].line_color = lambda a, b: b
    p.save(tmp_file('%s_colors_param_line_arity2b' % name))

    p = plot3d_parametric_line(
        sin(x) + 0.1 * sin(x) * cos(7 * x),
        cos(x) + 0.1 * cos(x) * cos(7 * x), 0.1 * sin(7 * x), (x, 0, 2 * pi))
    p[0].line_color = lambda a: sin(4 * a)
    p.save(tmp_file('%s_colors_3d_line_arity1' % name))
    p[0].line_color = lambda a, b: b
    p.save(tmp_file('%s_colors_3d_line_arity2' % name))
    p[0].line_color = lambda a, b, c: c
    p.save(tmp_file('%s_colors_3d_line_arity3' % name))

    p = plot3d(sin(x) * y, (x, 0, 6 * pi), (y, -5, 5))
    p[0].surface_color = lambda a: a
    p.save(tmp_file('%s_colors_surface_arity1' % name))
    p[0].surface_color = lambda a, b: b
    p.save(tmp_file('%s_colors_surface_arity2' % name))
    p[0].surface_color = lambda a, b, c: c
    p.save(tmp_file('%s_colors_surface_arity3a' % name))
    p[0].surface_color = lambda a, b, c: sqrt((a - 3 * pi)**2 + b**2)
    p.save(tmp_file('%s_colors_surface_arity3b' % name))

    p = plot3d_parametric_surface(x * cos(4 * y), x * sin(4 * y), y,
                                  (x, -1, 1), (y, -1, 1))
    p[0].surface_color = lambda a: a
    p.save(tmp_file('%s_colors_param_surf_arity1' % name))
    p[0].surface_color = lambda a, b: a * b
    p.save(tmp_file('%s_colors_param_surf_arity2' % name))
    p[0].surface_color = lambda a, b, c: sqrt(a**2 + b**2 + c**2)
    p.save(tmp_file('%s_colors_param_surf_arity3' % name))

    ###
    # Examples from the 'advanced' notebook
    ###

    i = Integral(log((sin(x)**2 + 1) * sqrt(x**2 + 1)), (x, 0, y))
    p = plot(i, (y, 1, 5))
    p.save(tmp_file('%s_advanced_integral' % name))

    s = summation(1 / x**y, (x, 1, oo))
    p = plot(s, (y, 2, 10))
    p.save(tmp_file('%s_advanced_inf_sum' % name))

    p = plot(summation(1 / x, (x, 1, y)), (y, 2, 10), show=False)
    p[0].only_integers = True
    p[0].steps = True
    p.save(tmp_file('%s_advanced_fin_sum' % name))

    ###
    # Test expressions that can not be translated to np and generate complex
    # results.
    ###
    plot(sin(x) + I * cos(x)).save(tmp_file())
    plot(sqrt(sqrt(-x))).save(tmp_file())
    plot(LambertW(x)).save(tmp_file())
    plot(sqrt(LambertW(x))).save(tmp_file())

    #Characteristic function of a StudentT distribution with nu=10
    plot((meijerg(
        ((1 / 2, ), ()),
        ((5, 0, 1 / 2), ()), 5 * x**2 * exp_polar(-I * pi) / 2) + meijerg(
            ((1 / 2, ), ()),
            ((5, 0, 1 / 2),
             ()), 5 * x**2 * exp_polar(I * pi) / 2)) / (48 * pi),
         (x, 1e-6, 1e-2)).save(tmp_file())
示例#46
0
def test_Mod1_behavior():
    from sympy import Symbol, simplify, lowergamma
    n = Symbol('n', integer=True)
    # Note: this should not hang.
    assert simplify(hyperexpand(meijerg([1], [], [n + 1], [0], z))) == \
        lowergamma(n + 1, z)
示例#47
0
 def u(an, ap, bm, bq):
     m = meijerg(an, ap, bm, bq, z)
     m2 = hyperexpand(m, allow_hyper=True)
     if m2.has(meijerg) and not (m2.is_Piecewise and len(m2.args) == 3):
         return False
     return tn(m, m2, z)
示例#48
0
def test_meijerint():
    from sympy import symbols, expand, arg
    s, t, mu = symbols('s t mu', real=True)
    assert integrate(
        meijerg([], [], [0], [], s * t) *
        meijerg([], [], [mu / 2], [-mu / 2], t**2 / 4),
        (t, 0, oo)).is_Piecewise
    s = symbols('s', positive=True)
    assert integrate(x**s*meijerg([[], []], [[0], []], x), (x, 0, oo)) == \
        gamma(s + 1)
    assert integrate(x**s * meijerg([[], []], [[0], []], x), (x, 0, oo),
                     meijerg=True) == gamma(s + 1)
    assert isinstance(
        integrate(x**s * meijerg([[], []], [[0], []], x), (x, 0, oo),
                  meijerg=False), Integral)

    assert meijerint_indefinite(exp(x), x) == exp(x)

    # TODO what simplifications should be done automatically?
    # This tests "extra case" for antecedents_1.
    a, b = symbols('a b', positive=True)
    assert simplify(meijerint_definite(x**a, x, 0, b)[0]) == \
        b**(a + 1)/(a + 1)

    # This tests various conditions and expansions:
    meijerint_definite((x + 1)**3 * exp(-x), x, 0, oo) == (16, True)

    # Again, how about simplifications?
    sigma, mu = symbols('sigma mu', positive=True)
    i, c = meijerint_definite(exp(-((x - mu) / (2 * sigma))**2), x, 0, oo)
    assert simplify(i) == sqrt(pi) * sigma * (erf(mu / (2 * sigma)) + 1)
    assert c == True

    i, _ = meijerint_definite(exp(-mu * x) * exp(sigma * x), x, 0, oo)
    # TODO it would be nice to test the condition
    assert simplify(i) == 1 / (mu - sigma)

    # Test substitutions to change limits
    assert meijerint_definite(exp(x), x, -oo, 2) == (exp(2), True)
    assert expand(meijerint_definite(exp(x), x, 0, I)[0]) == exp(I) - 1
    assert expand(meijerint_definite(exp(-x), x, 0, x)[0]) == \
        1 - exp(-exp(I*arg(x))*abs(x))

    # Test -oo to oo
    assert meijerint_definite(exp(-x**2), x, -oo, oo) == (sqrt(pi), True)
    assert meijerint_definite(exp(-abs(x)), x, -oo, oo) == (2, True)
    assert meijerint_definite(exp(-(2*x - 3)**2), x, -oo, oo) == \
        (sqrt(pi)/2, True)
    assert meijerint_definite(exp(-abs(2 * x - 3)), x, -oo, oo) == (1, True)
    assert meijerint_definite(
        exp(-((x - mu) / sigma)**2 / 2) / sqrt(2 * pi * sigma**2), x, -oo,
        oo) == (1, True)

    # Test one of the extra conditions for 2 g-functinos
    assert meijerint_definite(exp(-x) * sin(x), x, 0, oo) == (S(1) / 2, True)

    # Test a bug
    def res(n):
        return (1 / (1 + x**2)).diff(x, n).subs(x, 1) * (-1)**n

    for n in range(6):
        assert integrate(exp(-x)*sin(x)*x**n, (x, 0, oo), meijerg=True) == \
            res(n)

    # This used to test trigexpand... now it is done by linear substitution
    assert simplify(integrate(exp(-x) * sin(x + a), (x, 0, oo),
                              meijerg=True)) == sqrt(2) * sin(a + pi / 4) / 2

    # Test the condition 14 from prudnikov.
    # (This is besselj*besselj in disguise, to stop the product from being
    #  recognised in the tables.)
    a, b, s = symbols('a b s')
    from sympy import And, re
    assert meijerint_definite(meijerg([], [], [a/2], [-a/2], x/4)
                  *meijerg([], [], [b/2], [-b/2], x/4)*x**(s - 1), x, 0, oo) == \
        (4*2**(2*s - 2)*gamma(-2*s + 1)*gamma(a/2 + b/2 + s)
         /(gamma(-a/2 + b/2 - s + 1)*gamma(a/2 - b/2 - s + 1)
           *gamma(a/2 + b/2 - s + 1)),
            And(0 < -2*re(4*s) + 8, 0 < re(a/2 + b/2 + s), re(2*s) < 1))

    # test a bug
    assert integrate(sin(x**a)*sin(x**b), (x, 0, oo), meijerg=True) == \
        Integral(sin(x**a)*sin(x**b), (x, 0, oo))

    # test better hyperexpand
    assert integrate(exp(-x**2)*log(x), (x, 0, oo), meijerg=True) == \
        (sqrt(pi)*polygamma(0, S(1)/2)/4).expand()

    # Test hyperexpand bug.
    from sympy import lowergamma
    n = symbols('n', integer=True)
    assert simplify(integrate(exp(-x)*x**n, x, meijerg=True)) == \
        lowergamma(n + 1, x)

    # Test a bug with argument 1/x
    alpha = symbols('alpha', positive=True)
    assert meijerint_definite((2 - x)**alpha*sin(alpha/x), x, 0, 2) == \
        (sqrt(pi)*alpha*gamma(alpha + 1)*meijerg(((), (alpha/2 + S(1)/2,
        alpha/2 + 1)), ((0, 0, S(1)/2), (-S(1)/2,)), alpha**S(2)/16)/4, True)

    # test a bug related to 3016
    a, s = symbols('a s', positive=True)
    assert simplify(integrate(x**s*exp(-a*x**2), (x, -oo, oo))) == \
        a**(-s/2 - S(1)/2)*((-1)**s + 1)*gamma(s/2 + S(1)/2)/2
示例#49
0
def test_fresnel():
    assert fresnels(0) == 0
    assert fresnels(oo) == S.Half
    assert fresnels(-oo) == -S.Half

    assert fresnels(z) == fresnels(z)
    assert fresnels(-z) == -fresnels(z)
    assert fresnels(I * z) == -I * fresnels(z)
    assert fresnels(-I * z) == I * fresnels(z)

    assert conjugate(fresnels(z)) == fresnels(conjugate(z))

    assert fresnels(z).diff(z) == sin(pi * z**2 / 2)

    assert fresnels(z).rewrite(erf) == (S.One + I) / 4 * (erf(
        (S.One + I) / 2 * sqrt(pi) * z) - I * erf(
            (S.One - I) / 2 * sqrt(pi) * z))

    assert fresnels(z).rewrite(hyper) == \
        pi*z**3/6 * hyper([S(3)/4], [S(3)/2, S(7)/4], -pi**2*z**4/16)

    assert fresnels(z).series(z, n=15) == \
        pi*z**3/6 - pi**3*z**7/336 + pi**5*z**11/42240 + O(z**15)

    assert fresnels(w).is_real is True

    assert fresnels(z).as_real_imag() == \
        ((fresnels(re(z) - I*re(z)*Abs(im(z))/Abs(re(z)))/2 +
          fresnels(re(z) + I*re(z)*Abs(im(z))/Abs(re(z)))/2,
          I*(fresnels(re(z) - I*re(z)*Abs(im(z))/Abs(re(z))) -
          fresnels(re(z) + I*re(z)*Abs(im(z))/Abs(re(z)))) *
          re(z)*Abs(im(z))/(2*im(z)*Abs(re(z)))))

    assert fresnels(2 + 3 * I).as_real_imag() == (
        fresnels(2 + 3 * I) / 2 + fresnels(2 - 3 * I) / 2,
        I * (fresnels(2 - 3 * I) - fresnels(2 + 3 * I)) / 2)

    assert expand_func(integrate(fresnels(z), z)) == \
        z*fresnels(z) + cos(pi*z**2/2)/pi

    assert fresnels(z).rewrite(meijerg) == sqrt(2)*pi*z**(S(9)/4) * \
        meijerg(((), (1,)), ((S(3)/4,),
        (S(1)/4, 0)), -pi**2*z**4/16)/(2*(-z)**(S(3)/4)*(z**2)**(S(3)/4))

    assert fresnelc(0) == 0
    assert fresnelc(oo) == S.Half
    assert fresnelc(-oo) == -S.Half

    assert fresnelc(z) == fresnelc(z)
    assert fresnelc(-z) == -fresnelc(z)
    assert fresnelc(I * z) == I * fresnelc(z)
    assert fresnelc(-I * z) == -I * fresnelc(z)

    assert conjugate(fresnelc(z)) == fresnelc(conjugate(z))

    assert fresnelc(z).diff(z) == cos(pi * z**2 / 2)

    assert fresnelc(z).rewrite(erf) == (S.One - I) / 4 * (erf(
        (S.One + I) / 2 * sqrt(pi) * z) + I * erf(
            (S.One - I) / 2 * sqrt(pi) * z))

    assert fresnelc(z).rewrite(hyper) == \
        z * hyper([S.One/4], [S.One/2, S(5)/4], -pi**2*z**4/16)

    assert fresnelc(z).series(z, n=15) == \
        z - pi**2*z**5/40 + pi**4*z**9/3456 - pi**6*z**13/599040 + O(z**15)

    assert fresnelc(w).is_real is True

    assert fresnelc(z).as_real_imag() == \
        ((fresnelc(re(z) - I*re(z)*Abs(im(z))/Abs(re(z)))/2 +
          fresnelc(re(z) + I*re(z)*Abs(im(z))/Abs(re(z)))/2,
          I*(fresnelc(re(z) - I*re(z)*Abs(im(z))/Abs(re(z))) -
          fresnelc(re(z) + I*re(z)*Abs(im(z))/Abs(re(z)))) *
          re(z)*Abs(im(z))/(2*im(z)*Abs(re(z)))))

    assert fresnelc(2 + 3 * I).as_real_imag() == (
        fresnelc(2 - 3 * I) / 2 + fresnelc(2 + 3 * I) / 2,
        I * (fresnelc(2 - 3 * I) - fresnelc(2 + 3 * I)) / 2)

    assert expand_func(integrate(fresnelc(z), z)) == \
        z*fresnelc(z) - sin(pi*z**2/2)/pi

    assert fresnelc(z).rewrite(meijerg) == sqrt(2)*pi*z**(S(3)/4) * \
        meijerg(((), (1,)), ((S(1)/4,),
        (S(3)/4, 0)), -pi**2*z**4/16)/(2*(-z)**(S(1)/4)*(z**2)**(S(1)/4))

    from sympy.utilities.randtest import test_numerically

    test_numerically(re(fresnels(z)), fresnels(z).as_real_imag()[0], z)
    test_numerically(im(fresnels(z)), fresnels(z).as_real_imag()[1], z)
    test_numerically(fresnels(z), fresnels(z).rewrite(hyper), z)
    test_numerically(fresnels(z), fresnels(z).rewrite(meijerg), z)

    test_numerically(re(fresnelc(z)), fresnelc(z).as_real_imag()[0], z)
    test_numerically(im(fresnelc(z)), fresnelc(z).as_real_imag()[1], z)
    test_numerically(fresnelc(z), fresnelc(z).rewrite(hyper), z)
    test_numerically(fresnelc(z), fresnelc(z).rewrite(meijerg), z)
示例#50
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def test_meijerg_expand():
    from sympy import gammasimp, simplify

    # from mpmath docs
    assert hyperexpand(meijerg([[], []], [[0], []], -z)) == exp(z)

    assert hyperexpand(meijerg([[1, 1], []], [[1], [0]], z)) == log(z + 1)
    assert hyperexpand(meijerg([[1, 1], []], [[1], [1]], z)) == z / (z + 1)
    assert hyperexpand(meijerg([[], []], [[S.Half], [0]],
                               (z / 2)**2)) == sin(z) / sqrt(pi)
    assert hyperexpand(meijerg([[], []], [[0], [S.Half]],
                               (z / 2)**2)) == cos(z) / sqrt(pi)
    assert can_do_meijer([], [a], [a - 1, a - S.Half], [])
    assert can_do_meijer([], [], [a / 2], [-a / 2], False)  # branches...
    assert can_do_meijer([a], [b], [a], [b, a - 1])

    # wikipedia
    assert hyperexpand(meijerg([1], [], [], [0], z)) == Piecewise(
        (0, abs(z) < 1), (1, abs(1 / z) < 1),
        (meijerg([1], [], [], [0], z), True))
    assert hyperexpand(meijerg([], [1], [0], [], z)) == Piecewise(
        (1, abs(z) < 1), (0, abs(1 / z) < 1),
        (meijerg([], [1], [0], [], z), True))

    # The Special Functions and their Approximations
    assert can_do_meijer([], [], [a + b / 2], [a, a - b / 2, a + S.Half])
    assert can_do_meijer([], [], [a], [b],
                         False)  # branches only agree for small z
    assert can_do_meijer([], [S.Half], [a], [-a])
    assert can_do_meijer([], [], [a, b], [])
    assert can_do_meijer([], [], [a, b], [])
    assert can_do_meijer([], [], [a, a + S.Half], [b, b + S.Half])
    assert can_do_meijer([], [], [a, -a], [0, S.Half], False)  # dito
    assert can_do_meijer([], [], [a, a + S.Half, b, b + S.Half], [])
    assert can_do_meijer([S.Half], [], [0], [a, -a])
    assert can_do_meijer([S.Half], [], [a], [0, -a], False)  # dito
    assert can_do_meijer([], [a - S.Half], [a, b], [a - S.Half], False)
    assert can_do_meijer([], [a + S.Half], [a + b, a - b, a], [], False)
    assert can_do_meijer([a + S.Half], [], [b, 2 * a - b, a], [], False)

    # This for example is actually zero.
    assert can_do_meijer([], [], [], [a, b])

    # Testing a bug:
    assert hyperexpand(meijerg([0, 2], [], [], [-1, 1], z)) == Piecewise(
        (0, abs(z) < 1),
        (z / 2 - 1 / (2 * z), abs(1 / z) < 1),
        (meijerg([0, 2], [], [], [-1, 1], z), True),
    )

    # Test that the simplest possible answer is returned:
    assert (gammasimp(
        simplify(
            hyperexpand(
                meijerg([1], [1 - a], [-a / 2, -a / 2 + S.Half], [],
                        1 / z)))) == -2 * sqrt(pi) * (sqrt(z + 1) + 1)**a / a)

    # Test that hyper is returned
    assert (hyperexpand(meijerg([1], [], [a], [0, 0], z)) == hyper(
        (a, ), (a + 1, a + 1), z * exp_polar(I * pi)) * z**a * gamma(a) /
            gamma(a + 1)**2)

    # Test place option
    f = meijerg(((0, 1), ()), ((S.Half, ), (0, )), z**2)
    assert hyperexpand(f) == sqrt(pi) / sqrt(1 + z**(-2))
    assert hyperexpand(f, place=0) == sqrt(pi) * z / sqrt(z**2 + 1)
示例#51
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def test_meijer():
    raises(TypeError, 'meijerg(1, z)')
    raises(TypeError, 'meijerg(((1,), (2,)), (3,), (4,), z)')

    assert meijerg(((1, 2), (3,)), ((4,), (5,)), z) == \
           meijerg(Tuple(1, 2), Tuple(3), Tuple(4), Tuple(5), z)

    g = meijerg((1, 2), (3, 4, 5), (6, 7, 8, 9), (10, 11, 12, 13, 14), z)
    assert g.an == Tuple(1, 2)
    assert g.ap == Tuple(1, 2, 3, 4, 5)
    assert g.aother == Tuple(3, 4, 5)
    assert g.bm == Tuple(6, 7, 8, 9)
    assert g.bq == Tuple(6, 7, 8, 9, 10, 11, 12, 13, 14)
    assert g.bother == Tuple(10, 11, 12, 13, 14)
    assert g.argument == z
    assert g.nu == 75
    assert g.delta == -1

    assert meijerg([1, 2], [3], [4], [5], z).delta == S(1) / 2

    # just a few checks to make sure that all arguments go where they should
    assert tn(meijerg(Tuple(), Tuple(), Tuple(0), Tuple(), -z), exp(z), z)
    assert tn(
        sqrt(pi) *
        meijerg(Tuple(), Tuple(), Tuple(0), Tuple(S(1) / 2), z**2 / 4), cos(z),
        z)
    assert tn(meijerg(Tuple(1, 1), Tuple(), Tuple(1), Tuple(0), z), log(1 + z),
              z)

    # differentiation
    g = meijerg((randcplx(), ), (randcplx() + 2 * I, ), Tuple(),
                (randcplx(), randcplx()), z)
    assert td(g, z)

    g = meijerg(Tuple(), (randcplx(), ), Tuple(), (randcplx(), randcplx()), z)
    assert td(g, z)

    g = meijerg(Tuple(), Tuple(), Tuple(randcplx()),
                Tuple(randcplx(), randcplx()), z)
    assert td(g, z)

    a1, a2, b1, b2, c1, c2, d1, d2 = symbols('a1:3, b1:3, c1:3, d1:3')
    assert meijerg((a1, a2), (b1, b2), (c1, c2), (d1, d2), z).diff(z) == \
        (meijerg((a1-1, a2), (b1, b2), (c1, c2), (d1, d2), z) \
         + (a1 - 1)*meijerg((a1, a2), (b1, b2), (c1, c2), (d1, d2), z))/z

    raises(NotImplementedError, 'meijerg((z,), (), (), (), z).diff(z)')
示例#52
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def test_issue587(): # remove this when fresnel itegrals are implemented
    from sympy import meijerg
    assert integrate(sin(x**2), x) == \
           sqrt(2*pi)*meijerg([1], [], [S(3)/4], [S(1)/4, 0], x**4/4)/4
示例#53
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def test_atom_bug():
    from sympy import meijerg
    from sympy.integrals.heurisch import heurisch
    assert heurisch(meijerg([], [], [1], [], x), x) is None
def test_fresnel():
    assert fresnels(0) == 0
    assert fresnels(oo) == S.Half
    assert fresnels(-oo) == -S.Half

    assert fresnels(z) == fresnels(z)
    assert fresnels(-z) == -fresnels(z)
    assert fresnels(I * z) == -I * fresnels(z)
    assert fresnels(-I * z) == I * fresnels(z)

    assert conjugate(fresnels(z)) == fresnels(conjugate(z))

    assert fresnels(z).diff(z) == sin(pi * z**2 / 2)

    assert fresnels(z).rewrite(erf) == (S.One + I) / 4 * (erf(
        (S.One + I) / 2 * sqrt(pi) * z) - I * erf(
            (S.One - I) / 2 * sqrt(pi) * z))

    assert fresnels(z).rewrite(hyper) == \
        pi*z**3/6 * hyper([S(3)/4], [S(3)/2, S(7)/4], -pi**2*z**4/16)

    assert fresnels(z).series(z, n=15) == \
        pi*z**3/6 - pi**3*z**7/336 + pi**5*z**11/42240 + O(z**15)

    assert fresnels(w).is_real is True

    assert fresnels(z).as_real_imag() == \
        ((fresnels(re(z) - I*re(z)*Abs(im(z))/Abs(re(z)))/2 +
          fresnels(re(z) + I*re(z)*Abs(im(z))/Abs(re(z)))/2,
          I*(fresnels(re(z) - I*re(z)*Abs(im(z))/Abs(re(z))) -
          fresnels(re(z) + I*re(z)*Abs(im(z))/Abs(re(z)))) *
          re(z)*Abs(im(z))/(2*im(z)*Abs(re(z)))))

    assert fresnels(2 + 3 * I).as_real_imag() == (
        fresnels(2 + 3 * I) / 2 + fresnels(2 - 3 * I) / 2,
        I * (fresnels(2 - 3 * I) - fresnels(2 + 3 * I)) / 2)

    assert expand_func(integrate(fresnels(z), z)) == \
        z*fresnels(z) + cos(pi*z**2/2)/pi

    assert fresnels(z).rewrite(meijerg) == sqrt(2)*pi*z**(S(9)/4) * \
        meijerg(((), (1,)), ((S(3)/4,),
        (S(1)/4, 0)), -pi**2*z**4/16)/(2*(-z)**(S(3)/4)*(z**2)**(S(3)/4))

    assert fresnelc(0) == 0
    assert fresnelc(oo) == S.Half
    assert fresnelc(-oo) == -S.Half

    assert fresnelc(z) == fresnelc(z)
    assert fresnelc(-z) == -fresnelc(z)
    assert fresnelc(I * z) == I * fresnelc(z)
    assert fresnelc(-I * z) == -I * fresnelc(z)

    assert conjugate(fresnelc(z)) == fresnelc(conjugate(z))

    assert fresnelc(z).diff(z) == cos(pi * z**2 / 2)

    assert fresnelc(z).rewrite(erf) == (S.One - I) / 4 * (erf(
        (S.One + I) / 2 * sqrt(pi) * z) + I * erf(
            (S.One - I) / 2 * sqrt(pi) * z))

    assert fresnelc(z).rewrite(hyper) == \
        z * hyper([S.One/4], [S.One/2, S(5)/4], -pi**2*z**4/16)

    assert fresnelc(z).series(z, n=15) == \
        z - pi**2*z**5/40 + pi**4*z**9/3456 - pi**6*z**13/599040 + O(z**15)

    # issues 6510, 10102
    fs = (S.Half - sin(pi * z**2 / 2) / (pi**2 * z**3) +
          (-1 / (pi * z) + 3 / (pi**3 * z**5)) * cos(pi * z**2 / 2))
    fc = (S.Half - cos(pi * z**2 / 2) / (pi**2 * z**3) +
          (1 / (pi * z) - 3 / (pi**3 * z**5)) * sin(pi * z**2 / 2))
    assert fresnels(z).series(z, oo) == fs + O(z**(-6), (z, oo))
    assert fresnelc(z).series(z, oo) == fc + O(z**(-6), (z, oo))
    assert (fresnels(z).series(z, -oo) + fs.subs(z, -z)).expand().is_Order
    assert (fresnelc(z).series(z, -oo) + fc.subs(z, -z)).expand().is_Order
    assert (fresnels(1 / z).series(z) - fs.subs(z, 1 / z)).expand().is_Order
    assert (fresnelc(1 / z).series(z) - fc.subs(z, 1 / z)).expand().is_Order
    assert ((2 * fresnels(3 * z)).series(z, oo) -
            2 * fs.subs(z, 3 * z)).expand().is_Order
    assert ((3 * fresnelc(2 * z)).series(z, oo) -
            3 * fc.subs(z, 2 * z)).expand().is_Order

    assert fresnelc(w).is_real is True

    assert fresnelc(z).as_real_imag() == \
        ((fresnelc(re(z) - I*re(z)*Abs(im(z))/Abs(re(z)))/2 +
          fresnelc(re(z) + I*re(z)*Abs(im(z))/Abs(re(z)))/2,
          I*(fresnelc(re(z) - I*re(z)*Abs(im(z))/Abs(re(z))) -
          fresnelc(re(z) + I*re(z)*Abs(im(z))/Abs(re(z)))) *
          re(z)*Abs(im(z))/(2*im(z)*Abs(re(z)))))

    assert fresnelc(2 + 3 * I).as_real_imag() == (
        fresnelc(2 - 3 * I) / 2 + fresnelc(2 + 3 * I) / 2,
        I * (fresnelc(2 - 3 * I) - fresnelc(2 + 3 * I)) / 2)

    assert expand_func(integrate(fresnelc(z), z)) == \
        z*fresnelc(z) - sin(pi*z**2/2)/pi

    assert fresnelc(z).rewrite(meijerg) == sqrt(2)*pi*z**(S(3)/4) * \
        meijerg(((), (1,)), ((S(1)/4,),
        (S(3)/4, 0)), -pi**2*z**4/16)/(2*(-z)**(S(1)/4)*(z**2)**(S(1)/4))

    from sympy.utilities.randtest import verify_numerically

    verify_numerically(re(fresnels(z)), fresnels(z).as_real_imag()[0], z)
    verify_numerically(im(fresnels(z)), fresnels(z).as_real_imag()[1], z)
    verify_numerically(fresnels(z), fresnels(z).rewrite(hyper), z)
    verify_numerically(fresnels(z), fresnels(z).rewrite(meijerg), z)

    verify_numerically(re(fresnelc(z)), fresnelc(z).as_real_imag()[0], z)
    verify_numerically(im(fresnelc(z)), fresnelc(z).as_real_imag()[1], z)
    verify_numerically(fresnelc(z), fresnelc(z).rewrite(hyper), z)
    verify_numerically(fresnelc(z), fresnelc(z).rewrite(meijerg), z)