Beispiel #1
0
def test_sympyissue_4559():
    e = Symbol('e')
    w = Wild('w', exclude=[x])
    y = Wild('y')

    # this is as it should be

    assert (3/x).match(w/y) == {w: 3, y: x}
    assert (3*x).match(w*y) == {w: 3, y: x}
    assert (x/3).match(y/w) == {w: 3, y: x}
    assert (3*x).match(y/w) == {w: Rational(1, 3), y: x}

    # these could be allowed to fail

    assert (x/3).match(w/y) == {w: Rational(1, 3), y: 1/x}
    assert (3*x).match(w/y) == {w: 3, y: 1/x}
    assert (3/x).match(w*y) == {w: 3, y: 1/x}

    # Note that solve will give
    # multiple roots but match only gives one:
    #
    # >>> solve(x**r - y**2, y)
    # [{y: -x**(r/2)}, {y: x**(r/2)}]

    r = Symbol('r', rational=True)
    assert (x**r).match(y**2) == {y: x**(r/2)}
    assert (x**e).match(y**2) == {y: sqrt(x**e)}

    # since (x**i = y) -> x = y**(1/i) where i is an integer
    # the following should also be valid as long as y is not
    # zero when i is negative.

    a = Wild('a')

    e = Integer(0)
    assert e.match(a) == {a: e}
    assert e.match(1/a) is None
    assert e.match(a**.3) is None

    e = Integer(3)
    assert e.match(1/a) == {a: 1/e}
    assert e.match(1/a**2) == {a: 1/sqrt(e)}
    e = pi
    assert e.match(1/a) == {a: 1/e}
    assert e.match(1/a**2) == {a: 1/sqrt(e)}
    assert (-e).match(sqrt(a)) is None
    assert (-e).match(a**2) == {a: I*sqrt(pi)}
Beispiel #2
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def test_abs1():
    a = Symbol("a", extended_real=True)
    b = Symbol("b", extended_real=True)
    assert abs(a) == abs(a)
    assert abs(-a) == abs(a)
    assert abs(a + I * b) == sqrt(a**2 + b**2)
Beispiel #3
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def test_re_im1652():
    x = Symbol('x')
    assert re(x) == re(conjugate(x))
    assert im(x) == -im(conjugate(x))
    assert im(x) * re(conjugate(x)) + im(conjugate(x)) * re(x) == 0
Beispiel #4
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def test_I():
    y = Symbol("y")
    assert gruntz(I*x, x) == I*oo
    assert gruntz(y*I*x, x) == sign(y)*I*oo
    assert gruntz(y*3*I*x, x) == sign(y)*I*oo
    assert gruntz(y*3*sin(I)*x, x).simplify() == sign(y)*I*oo
Beispiel #5
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def test_limit_bug():
    z = Symbol('z', nonzero=True)
    assert integrate(sin(x*y*z), (x, 0, pi), (y, 0, pi)) == \
        (log(z**2) + 2*EulerGamma + 2*log(pi))/(2*z) - \
        (-log(pi*z) + log(pi**2*z**2)/2 + Ci(pi**2*z))/z + log(pi)/z
Beispiel #6
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def test_sympyissue_4376():
    n = Symbol('n', integer=True, positive=True)
    assert simplify(integrate(n*(x**(1/n) - 1), (x, 0, Rational(1, 2))) -
                    (n**2 - 2**(1/n)*n**2 - n*2**(1/n))/(2**(1 + 1/n) + n*2**(1 + 1/n))) == 0
Beispiel #7
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def test_sympyissue_3664():
    n = Symbol('n', integer=True, nonzero=True)
    assert integrate(-1./2 * x * sin(n * pi * x/2), [x, -2, 0]) == \
        2*cos(pi*n)/(pi*n)
    assert integrate(-x*sin(n*pi*x/2)/2, [x, -2, 0]) == \
        2*cos(pi*n)/(pi*n)
Beispiel #8
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def test_sympyissue_4803():
    x_max = Symbol('x_max')
    assert integrate(y/pi*exp(-(x_max - x)/cos(a)), x) == \
        y*exp((x - x_max)/cos(a))*cos(a)/pi
Beispiel #9
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def test_negative_one():
    x = Symbol('x', complex=True)
    y = Symbol('y', complex=True)
    assert 1/x**y == x**(-y)
Beispiel #10
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def test_sympyissue_8650():
    n = Symbol('n', integer=True, nonnegative=True)
    assert (n**n).is_positive is True
    x = 5*n+5
    assert (x**(5*(n+1))).is_positive is True
Beispiel #11
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def test_power_with_noncommutative_mul_as_base():
    x = Symbol('x', commutative=False)
    y = Symbol('y', commutative=False)
    assert not (x*y)**3 == x**3*y**3
    assert (2*x*y)**3 == 8*(x*y)**3
Beispiel #12
0
from diofant import Rational, Symbol
from diofant.geometry import Circle, Line, Point, Polygon, Segment
from diofant.sets import FiniteSet, Union, Intersection, EmptySet

x = Symbol('x', real=True)
y = Symbol('y', real=True)
z = Symbol('z', real=True)
t = Symbol('t', real=True)
k = Symbol('k', real=True)
x1 = Symbol('x1', real=True)
x2 = Symbol('x2', real=True)
x3 = Symbol('x3', real=True)
y1 = Symbol('y1', real=True)
y2 = Symbol('y2', real=True)
y3 = Symbol('y3', real=True)
z1 = Symbol('z1', real=True)
z2 = Symbol('z2', real=True)
z3 = Symbol('z3', real=True)
half = Rational(1, 2)

p1, p2, p3, p4 = map(Point, [(0, 0), (1, 0), (5, 1), (0, 1)])
p5, p6, p7 = map(Point, [(3, 2), (1, -1), (0, 2)])
l1 = Line(Point(0, 0), Point(1, 1))
l2 = Line(Point(half, half), Point(5, 5))
l3 = Line(p2, p3)
l4 = Line(p3, p4)
poly1 = Polygon(p1, p2, p3, p4)
poly2 = Polygon(p5, p6, p7)
poly3 = Polygon(p1, p2, p5)

Beispiel #13
0
def test_residue():
    assert n_order(2, 13) == 12
    assert [n_order(a, 7) for a in range(1, 7)] == \
           [1, 3, 6, 3, 6, 2]
    assert n_order(5, 17) == 16
    assert n_order(17, 11) == n_order(6, 11)
    assert n_order(101, 119) == 6
    assert n_order(11, (10**50 + 151)**2) == 10000000000000000000000000000000000000000000000030100000000000000000000000000000000000000000000022650
    pytest.raises(ValueError, lambda: n_order(6, 9))

    assert is_primitive_root(2, 7) is False
    assert is_primitive_root(3, 8) is False
    assert is_primitive_root(11, 14) is False
    assert is_primitive_root(12, 17) == is_primitive_root(29, 17)
    pytest.raises(ValueError, lambda: is_primitive_root(3, 6))

    assert [primitive_root(i) for i in range(2, 31)] == [1, 2, 3, 2, 5, 3,
                                                         None, 2, 3, 2, None, 2, 3, None, None, 3, 5, 2, None, None, 7, 5,
                                                         None, 2, 7, 2, None, 2, None]

    for p in primerange(3, 100):
        it = _primitive_root_prime_iter(p)
        assert len(list(it)) == totient(totient(p))
    assert primitive_root(97) == 5
    assert primitive_root(97**2) == 5
    assert primitive_root(40487) == 5
    # note that primitive_root(40487) + 40487 = 40492 is a primitive root
    # of 40487**2, but it is not the smallest
    assert primitive_root(40487**2) == 10
    assert primitive_root(82) == 7
    p = 10**50 + 151
    assert primitive_root(p) == 11
    assert primitive_root(2*p) == 11
    assert primitive_root(p**2) == 11
    pytest.raises(ValueError, lambda: primitive_root(-3))

    assert is_quad_residue(3, 7) is False
    assert is_quad_residue(10, 13) is True
    assert is_quad_residue(12364, 139) == is_quad_residue(12364 % 139, 139)
    assert is_quad_residue(207, 251) is True
    assert is_quad_residue(0, 1) is True
    assert is_quad_residue(1, 1) is True
    assert is_quad_residue(0, 2) == is_quad_residue(1, 2) is True
    assert is_quad_residue(1, 4) is True
    assert is_quad_residue(2, 27) is False
    assert is_quad_residue(13122380800, 13604889600) is True
    assert [j for j in range(14) if is_quad_residue(j, 14)] == \
           [0, 1, 2, 4, 7, 8, 9, 11]
    pytest.raises(ValueError, lambda: is_quad_residue(1.1, 2))
    pytest.raises(ValueError, lambda: is_quad_residue(2, 0))

    assert quadratic_residues(12) == [0, 1, 4, 9]
    assert quadratic_residues(13) == [0, 1, 3, 4, 9, 10, 12]
    assert [len(quadratic_residues(i)) for i in range(1, 20)] == \
        [1, 2, 2, 2, 3, 4, 4, 3, 4, 6, 6, 4, 7, 8, 6, 4, 9, 8, 10]

    assert list(sqrt_mod_iter(6, 2)) == [0]
    assert sqrt_mod(3, 13) == 4
    assert sqrt_mod(3, -13) == 4
    assert sqrt_mod(6, 23) == 11
    assert sqrt_mod(345, 690) == 345
    assert sqrt_mod(9, 18) == 3

    for p in range(3, 100):
        d = collections.defaultdict(list)
        for i in range(p):
            d[pow(i, 2, p)].append(i)
        for i in range(1, p):
            it = sqrt_mod_iter(i, p)
            v = sqrt_mod(i, p, True)
            if v:
                v = sorted(v)
                assert d[i] == v
            else:
                assert not d[i]

    assert sqrt_mod(9, 27, True) == [3, 6, 12, 15, 21, 24]
    assert sqrt_mod(9, 81, True) == [3, 24, 30, 51, 57, 78]
    assert sqrt_mod(9, 3**5, True) == [3, 78, 84, 159, 165, 240]
    assert sqrt_mod(81, 3**4, True) == [0, 9, 18, 27, 36, 45, 54, 63, 72]
    assert sqrt_mod(81, 3**5, True) == [9, 18, 36, 45, 63, 72, 90, 99, 117,
                                        126, 144, 153, 171, 180, 198, 207, 225, 234]
    assert sqrt_mod(81, 3**6, True) == [9, 72, 90, 153, 171, 234, 252, 315,
                                        333, 396, 414, 477, 495, 558, 576, 639, 657, 720]
    assert sqrt_mod(81, 3**7, True) == [9, 234, 252, 477, 495, 720, 738, 963,
                                        981, 1206, 1224, 1449, 1467, 1692, 1710, 1935, 1953, 2178]

    for a, p in [(26214400, 32768000000), (26214400, 16384000000),
                 (262144, 1048576), (87169610025, 163443018796875),
                 (22315420166400, 167365651248000000)]:
        assert pow(sqrt_mod(a, p), 2, p) == a

    n = 70
    a, p = 5**2*3**n*2**n, 5**6*3**(n+1)*2**(n+2)
    it = sqrt_mod_iter(a, p)
    for i in range(10):
        assert pow(next(it), 2, p) == a
    a, p = 5**2*3**n*2**n, 5**6*3**(n+1)*2**(n+3)
    it = sqrt_mod_iter(a, p)
    for i in range(2):
        assert pow(next(it), 2, p) == a
    n = 100
    a, p = 5**2*3**n*2**n, 5**6*3**(n+1)*2**(n+1)
    it = sqrt_mod_iter(a, p)
    for i in range(2):
        assert pow(next(it), 2, p) == a

    assert type(next(sqrt_mod_iter(9, 27))) is int
    assert isinstance(next(sqrt_mod_iter(9, 27, ZZ)), type(ZZ(1)))
    assert isinstance(next(sqrt_mod_iter(1, 7, ZZ)), type(ZZ(1)))

    assert list(sqrt_mod_iter(4, 919, ZZ)) == [2, 917]
    assert list(sqrt_mod_iter(6, 146, ZZ)) == [88, 58]

    pytest.raises(ValueError, lambda: is_nthpow_residue(+2, +1, 0))
    pytest.raises(ValueError, lambda: is_nthpow_residue(+2, -1, 5))
    pytest.raises(ValueError, lambda: is_nthpow_residue(-2, +1, 5))

    assert is_nthpow_residue(2, 1, 5)

    assert is_nthpow_residue(1, 0, 1) is False
    assert is_nthpow_residue(1, 0, 2) is True
    assert is_nthpow_residue(3, 0, 2) is False
    assert is_nthpow_residue(0, 1, 8) is True
    assert is_nthpow_residue(2, 3, 2) is False
    assert is_nthpow_residue(2, 3, 9) is False
    assert is_nthpow_residue(3, 5, 30) is True
    assert is_nthpow_residue(21, 11, 20) is True
    assert is_nthpow_residue(7, 10, 20) is False
    assert is_nthpow_residue(5, 10, 20) is True
    assert is_nthpow_residue(3, 10, 48) is False
    assert is_nthpow_residue(1, 10, 40) is True
    assert is_nthpow_residue(3, 10, 24) is False
    assert is_nthpow_residue(1, 10, 24) is True
    assert is_nthpow_residue(3, 10, 24) is False
    assert is_nthpow_residue(2, 10, 48) is False
    assert is_nthpow_residue(81, 3, 972) is False
    assert is_nthpow_residue(243, 5, 5103) is True
    assert is_nthpow_residue(243, 3, 1240029) is False
    assert {a for a in range(1024)
            if is_nthpow_residue(a, 56, 1024)} == {pow(i, 56, 1024)
                                                   for i in range(1024)}
    assert {a for a in range(2048)
            if is_nthpow_residue(a, 256, 2048)} == {pow(i, 256, 2048)
                                                    for i in range(2048)}
    x = {pow(i, 11, 324000) for i in range(1000)}
    assert [is_nthpow_residue(a, 11, 324000) for a in x]
    x = {pow(i, 17, 22217575536) for i in range(1000)}
    assert [is_nthpow_residue(a, 17, 22217575536) for a in x]
    assert is_nthpow_residue(676, 3, 5364)
    assert is_nthpow_residue(9, 12, 36)
    assert is_nthpow_residue(32, 10, 41)
    assert is_nthpow_residue(4, 2, 64)
    assert is_nthpow_residue(31, 4, 41)

    assert not is_nthpow_residue(2, 2, 5)
    assert is_nthpow_residue(8547, 12, 10007)
    assert nthroot_mod(1801, 11, 2663) == 44
    for a, q, p in [(51922, 2, 203017), (43, 3, 109), (1801, 11, 2663),
                    (26118163, 1303, 33333347), (1499, 7, 2663), (595, 6, 2663),
                    (1714, 12, 2663), (28477, 9, 33343)]:
        r = nthroot_mod(a, q, p)
        assert pow(r, q, p) == a
    assert nthroot_mod(11, 3, 109) is None
    assert nthroot_mod(6, 12, 5) == 1
    pytest.raises(NotImplementedError, lambda: nthroot_mod(16, 5, 36))
    pytest.raises(NotImplementedError, lambda: nthroot_mod(9, 16, 36))

    for p in primerange(5, 100):
        qv = range(3, p, 4)
        for q in qv:
            d = collections.defaultdict(list)
            for i in range(p):
                d[pow(i, q, p)].append(i)
            for a in range(1, p - 1):
                res = nthroot_mod(a, q, p, True)
                if d[a]:
                    assert d[a] == res
                else:
                    assert res is None

    assert legendre_symbol(5, 11) == 1
    assert legendre_symbol(25, 41) == 1
    assert legendre_symbol(67, 101) == -1
    assert legendre_symbol(0, 13) == 0
    assert legendre_symbol(9, 3) == 0
    pytest.raises(ValueError, lambda: legendre_symbol(2, 4))

    assert jacobi_symbol(25, 41) == 1
    assert jacobi_symbol(-23, 83) == -1
    assert jacobi_symbol(3, 9) == 0
    assert jacobi_symbol(42, 97) == -1
    assert jacobi_symbol(3, 5) == -1
    assert jacobi_symbol(7, 9) == 1
    assert jacobi_symbol(0, 3) == 0
    assert jacobi_symbol(0, 1) == 1
    assert jacobi_symbol(2, 1) == 1
    assert jacobi_symbol(1, 3) == 1
    pytest.raises(ValueError, lambda: jacobi_symbol(3, 8))

    assert mobius(13*7) == 1
    assert mobius(1) == 1
    assert mobius(13*7*5) == -1
    assert mobius(13**2) == 0
    pytest.raises(ValueError, lambda: mobius(-3))

    p = Symbol('p', integer=True, positive=True, prime=True)
    x = Symbol('x', positive=True)
    i = Symbol('i', integer=True)
    assert mobius(p) == -1
    pytest.raises(TypeError, lambda: mobius(x))
    pytest.raises(ValueError, lambda: mobius(i))
    mobius(Symbol('p', positive=True, integer=True))

    assert _discrete_log_trial_mul(41, 15, 7) == 3
    assert _discrete_log_trial_mul(587, 2**7, 2) == 7
    assert _discrete_log_trial_mul(941, 7**18, 7) == 18
    assert _discrete_log_trial_mul(389, 3**81, 3) == 81
    assert _discrete_log_trial_mul(191, 19**123, 19) == 123
    pytest.raises(ValueError, lambda: _discrete_log_trial_mul(11, 7, 31))

    assert _discrete_log_shanks_steps(41, 15, 7) == 3
    assert _discrete_log_shanks_steps(442879, 7**2, 7) == 2
    assert _discrete_log_shanks_steps(874323, 5**19, 5) == 19
    assert _discrete_log_shanks_steps(6876342, 7**71, 7) == 71
    assert _discrete_log_shanks_steps(2456747, 3**321, 3) == 321
    pytest.raises(ValueError, lambda: _discrete_log_shanks_steps(11, 7, 31))

    assert _discrete_log_pohlig_hellman(251, 210, 71) == 197
    assert _discrete_log_pohlig_hellman(98376431, 11**9, 11) == 9
    assert _discrete_log_pohlig_hellman(78723213, 11**31, 11) == 31
    assert _discrete_log_pohlig_hellman(32942478, 11**98, 11) == 98
    assert _discrete_log_pohlig_hellman(14789363, 11**444, 11) == 444
    pytest.raises(ValueError, lambda: _discrete_log_pohlig_hellman(11, 7, 31))

    assert discrete_log(587, 2**9, 2) == 9
    assert discrete_log(2456747, 3**51, 3) == 51
    assert discrete_log(32942478, 11**127, 11) == 127
    assert discrete_log(432751500361, 7**324, 7) == 324
    pytest.raises(ValueError, lambda: discrete_log(11, 7, 31))
Beispiel #14
0
def test_deriv_noncommutative():
    A = Symbol("A", commutative=False)
    f = Function("f")
    x = Symbol("x")
    assert A * f(x) * A == f(x) * A**2
    assert A * f(x).diff(x) * A == f(x).diff(x) * A**2
Beispiel #15
0
def test_speed():
    # this should return in 0.0s. If it takes forever, it's wrong.
    x = Symbol("x")
    assert x.diff(x, 10**8) == 0
Beispiel #16
0
def test_speed():
    # this should return in 0.0s. If it takes forever, it's wrong.
    x = Symbol("x")
    assert x.diff(x, 10**8) == 0
Beispiel #17
0
def test_expevalbug():
    x = Symbol("x")
    e1 = exp(1*x)
    e3 = exp(x)
    assert e1 == e3
Beispiel #18
0
def test_sympyissue_4362():
    neg = Symbol('neg', negative=True)
    nonneg = Symbol('nonneg', nonnegative=True)
    any = Symbol('any')
    num, den = sqrt(1/neg).as_numer_denom()
    assert num == sqrt(-1)
    assert den == sqrt(-neg)
    num, den = sqrt(1/nonneg).as_numer_denom()
    assert num == 1
    assert den == sqrt(nonneg)
    num, den = sqrt(1/any).as_numer_denom()
    assert num == sqrt(1/any)
    assert den == 1

    def eqn(num, den, pow):
        return (num/den)**pow
    npos = 1
    nneg = -1
    dpos = 2 - sqrt(3)
    dneg = 1 - sqrt(3)
    assert dpos > 0 and dneg < 0 and npos > 0 and nneg < 0
    # pos or neg integer
    eq = eqn(npos, dpos, 2)
    assert eq.is_Pow and eq.as_numer_denom() == (1, dpos**2)
    eq = eqn(npos, dneg, 2)
    assert eq.is_Pow and eq.as_numer_denom() == (1, dneg**2)
    eq = eqn(nneg, dpos, 2)
    assert eq.is_Pow and eq.as_numer_denom() == (1, dpos**2)
    eq = eqn(nneg, dneg, 2)
    assert eq.is_Pow and eq.as_numer_denom() == (1, dneg**2)
    eq = eqn(npos, dpos, -2)
    assert eq.is_Pow and eq.as_numer_denom() == (dpos**2, 1)
    eq = eqn(npos, dneg, -2)
    assert eq.is_Pow and eq.as_numer_denom() == (dneg**2, 1)
    eq = eqn(nneg, dpos, -2)
    assert eq.is_Pow and eq.as_numer_denom() == (dpos**2, 1)
    eq = eqn(nneg, dneg, -2)
    assert eq.is_Pow and eq.as_numer_denom() == (dneg**2, 1)
    # pos or neg rational
    pow = Rational(1, 2)
    eq = eqn(npos, dpos, pow)
    assert eq.is_Pow and eq.as_numer_denom() == (npos**pow, dpos**pow)
    eq = eqn(npos, dneg, pow)
    assert eq.is_Pow is False and eq.as_numer_denom() == ((-npos)**pow, (-dneg)**pow)
    eq = eqn(nneg, dpos, pow)
    assert not eq.is_Pow or eq.as_numer_denom() == (nneg**pow, dpos**pow)
    eq = eqn(nneg, dneg, pow)
    assert eq.is_Pow and eq.as_numer_denom() == ((-nneg)**pow, (-dneg)**pow)
    eq = eqn(npos, dpos, -pow)
    assert eq.is_Pow and eq.as_numer_denom() == (dpos**pow, npos**pow)
    eq = eqn(npos, dneg, -pow)
    assert eq.is_Pow is False and eq.as_numer_denom() == (-(-npos)**pow*(-dneg)**pow, npos)
    eq = eqn(nneg, dpos, -pow)
    assert not eq.is_Pow or eq.as_numer_denom() == (dpos**pow, nneg**pow)
    eq = eqn(nneg, dneg, -pow)
    assert eq.is_Pow and eq.as_numer_denom() == ((-dneg)**pow, (-nneg)**pow)
    # unknown exponent
    pow = 2*any
    eq = eqn(npos, dpos, pow)
    assert eq.is_Pow and eq.as_numer_denom() == (npos**pow, dpos**pow)
    eq = eqn(npos, dneg, pow)
    assert eq.is_Pow and eq.as_numer_denom() == ((-npos)**pow, (-dneg)**pow)
    eq = eqn(nneg, dpos, pow)
    assert eq.is_Pow and eq.as_numer_denom() == (nneg**pow, dpos**pow)
    eq = eqn(nneg, dneg, pow)
    assert eq.is_Pow and eq.as_numer_denom() == ((-nneg)**pow, (-dneg)**pow)
    eq = eqn(npos, dpos, -pow)
    assert eq.as_numer_denom() == (dpos**pow, npos**pow)
    eq = eqn(npos, dneg, -pow)
    assert eq.is_Pow and eq.as_numer_denom() == ((-dneg)**pow, (-npos)**pow)
    eq = eqn(nneg, dpos, -pow)
    assert eq.is_Pow and eq.as_numer_denom() == (dpos**pow, nneg**pow)
    eq = eqn(nneg, dneg, -pow)
    assert eq.is_Pow and eq.as_numer_denom() == ((-dneg)**pow, (-nneg)**pow)

    assert ((1/(1 + x/3))**-1).as_numer_denom() == (3 + x, 3)
    notp = Symbol('notp', positive=False)  # not positive does not imply real
    b = ((1 + x/notp)**-2)
    assert (b**(-y)).as_numer_denom() == (1, b**y)
    assert (b**-1).as_numer_denom() == ((notp + x)**2, notp**2)
    nonp = Symbol('nonp', nonpositive=True)
    assert (((1 + x/nonp)**-2)**-1).as_numer_denom() == ((-nonp - x)**2,
                                                         nonp**2)

    n = Symbol('n', negative=True)
    assert (x**n).as_numer_denom() == (1, x**-n)
    assert sqrt(1/n).as_numer_denom() == (I, sqrt(-n))
    n = Symbol('0 or neg', nonpositive=True)
    # if x and n are split up without negating each term and n is negative
    # then the answer might be wrong; if n is 0 it won't matter since
    # 1/oo and 1/zoo are both zero as is sqrt(0)/sqrt(-x) unless x is also
    # zero (in which case the negative sign doesn't matter):
    # 1/sqrt(1/-1) = -I but sqrt(-1)/sqrt(1) = I
    assert (1/sqrt(x/n)).as_numer_denom() == (sqrt(-n), sqrt(-x))
    c = Symbol('c', complex=True)
    e = sqrt(1/c)
    assert e.as_numer_denom() == (e, 1)
    i = Symbol('i', integer=True)
    assert (((1 + x/y)**i)).as_numer_denom() == ((x + y)**i, y**i)
Beispiel #19
0
def test_sympyissue_13501():
    a = Symbol('a', real=True)
    assert integrate(1/(1 + a**2*x**2), x) == atan(a*x)/a
import pytest

from diofant import (Symbol, gamma, I, oo, nan, zoo, factorial, sqrt, Rational,
                     log, Integer, polygamma, EulerGamma, pi, uppergamma, S,
                     expand_func, loggamma, sin, cos, O, lowergamma, exp, erf,
                     exp_polar, harmonic, zeta, conjugate, trigamma)
from diofant.core.function import ArgumentIndexError
from diofant.utilities.randtest import (test_derivative_numerically as td,
                                        random_complex_number as randcplx,
                                        verify_numerically as tn)

__all__ = ()

x = Symbol('x')
y = Symbol('y')
n = Symbol('n', integer=True)
w = Symbol('w', extended_real=True)


def test_gamma():
    assert gamma(nan) == nan
    assert gamma(oo) == oo

    assert gamma(-100) == zoo
    assert gamma(0) == zoo

    assert gamma(1) == 1
    assert gamma(2) == 1
    assert gamma(3) == 2

    assert gamma(102) == factorial(101)
Beispiel #21
0
def test_sympyissue_4100():
    R = Symbol('R', positive=True)
    assert integrate(sqrt(R**2 - x**2), (x, 0, R)) == pi*R**2/4
def test_polygamma():
    from diofant import I

    assert polygamma(n, nan) == nan

    assert polygamma(0, oo) == oo
    assert polygamma(0, -oo) == oo
    assert polygamma(0, I * oo) == oo
    assert polygamma(0, -I * oo) == oo
    assert polygamma(1, oo) == 0
    assert polygamma(5, oo) == 0

    assert polygamma(0, -9) == zoo

    assert polygamma(0, -9) == zoo
    assert polygamma(0, -1) == zoo

    assert polygamma(0, 0) == zoo

    assert polygamma(0, 1) == -EulerGamma
    assert polygamma(0, 7) == Rational(49, 20) - EulerGamma

    assert polygamma(1, 1) == pi**2 / 6
    assert polygamma(1, 2) == pi**2 / 6 - 1
    assert polygamma(1, 3) == pi**2 / 6 - Rational(5, 4)
    assert polygamma(3, 1) == pi**4 / 15
    assert polygamma(3, 5) == 6 * (Rational(-22369, 20736) + pi**4 / 90)
    assert polygamma(5, 1) == 8 * pi**6 / 63
    assert trigamma(x) == polygamma(1, x)

    def t(m, n):
        x = Integer(m) / n
        r = polygamma(0, x)
        if r.has(polygamma):
            return False
        return abs(polygamma(0, x.n()).n() - r.n()).n() < 1e-10

    assert t(1, 2)
    assert t(3, 2)
    assert t(-1, 2)
    assert t(1, 4)
    assert t(-3, 4)
    assert t(1, 3)
    assert t(4, 3)
    assert t(3, 4)
    assert t(2, 3)

    assert polygamma(0, x).rewrite(zeta) == polygamma(0, x)
    assert polygamma(1, x).rewrite(zeta) == zeta(2, x)
    assert polygamma(2, x).rewrite(zeta) == -2 * zeta(3, x)

    assert polygamma(3, 7 * x).diff(x) == 7 * polygamma(4, 7 * x)

    assert polygamma(0, x).rewrite(harmonic) == harmonic(x - 1) - EulerGamma
    assert polygamma(
        2, x).rewrite(harmonic) == 2 * harmonic(x - 1, 3) - 2 * zeta(3)
    ni = Symbol("n", integer=True)
    assert polygamma(
        ni,
        x).rewrite(harmonic) == (-1)**(ni + 1) * (-harmonic(x - 1, ni + 1) +
                                                  zeta(ni + 1)) * factorial(ni)

    # Polygamma of non-negative integer order is unbranched:
    from diofant import exp_polar
    k = Symbol('n', integer=True, nonnegative=True)
    assert polygamma(k, exp_polar(2 * I * pi) * x) == polygamma(k, x)

    # but negative integers are branched!
    k = Symbol('n', integer=True)
    assert polygamma(k,
                     exp_polar(2 * I * pi) *
                     x).args == (k, exp_polar(2 * I * pi) * x)

    # Polygamma of order -1 is loggamma:
    assert polygamma(-1, x) == loggamma(x)

    # But smaller orders are iterated integrals and don't have a special name
    assert polygamma(-2, x).func is polygamma

    # Test a bug
    assert polygamma(0, -x).expand(func=True) == polygamma(0, -x)

    assert polygamma(1, x).as_leading_term(x) == polygamma(1, x)
Beispiel #23
0
def test_sympyissue_5907():
    a = Symbol('a', real=True)
    assert (integrate(1/(x**2 + a**2)**2, x) ==
            x/(2*a**4 + 2*a**2*x**2) + atan(x/a)/(2*a**3))
def test_loggamma():
    pytest.raises(TypeError, lambda: loggamma(2, 3))
    pytest.raises(ArgumentIndexError, lambda: loggamma(x).fdiff(2))

    assert loggamma(-1) == oo
    assert loggamma(-2) == oo
    assert loggamma(0) == oo
    assert loggamma(1) == 0
    assert loggamma(2) == 0
    assert loggamma(3) == log(2)
    assert loggamma(4) == log(6)

    n = Symbol("n", integer=True, positive=True)
    assert loggamma(n) == log(gamma(n))
    assert loggamma(-n) == oo
    assert loggamma(n / 2) == log(2**(-n + 1) * sqrt(pi) * gamma(n) /
                                  gamma(n / 2 + S.Half))

    from diofant import I

    assert loggamma(oo) == oo
    assert loggamma(-oo) == zoo
    assert loggamma(I * oo) == zoo
    assert loggamma(-I * oo) == zoo
    assert loggamma(zoo) == zoo
    assert loggamma(nan) == nan

    L = loggamma(Rational(16, 3))
    E = -5 * log(3) + loggamma(Rational(
        1, 3)) + log(4) + log(7) + log(10) + log(13)
    assert expand_func(L).doit() == E
    assert L.n() == E.n()

    L = loggamma(19 / Integer(4))
    E = -4 * log(4) + loggamma(Rational(
        3, 4)) + log(3) + log(7) + log(11) + log(15)
    assert expand_func(L).doit() == E
    assert L.n() == E.n()

    L = loggamma(Rational(23, 7))
    E = -3 * log(7) + log(2) + loggamma(Rational(2, 7)) + log(9) + log(16)
    assert expand_func(L).doit() == E
    assert L.n() == E.n()

    L = loggamma(19 / Integer(4) - 7)
    E = -log(9) - log(5) + loggamma(Rational(3, 4)) + 3 * log(4) - 3 * I * pi
    assert expand_func(L).doit() == E
    assert L.n() == E.n()

    L = loggamma(23 / Integer(7) - 6)
    E = -log(19) - log(12) - log(5) + loggamma(Rational(
        2, 7)) + 3 * log(7) - 3 * I * pi
    assert expand_func(L).doit() == E
    assert L.n() == E.n()

    assert expand_func(loggamma(x)) == loggamma(x)
    assert expand_func(loggamma(1 / Integer(3))) == loggamma(1 / Integer(3))

    assert loggamma(x).diff(x) == polygamma(0, x)
    s1 = loggamma(1 / (x + sin(x)) + cos(x)).nseries(x, n=4)
    s2 = (-log(2*x) - 1)/(2*x) - log(x/pi)/2 + (4 - log(2*x))*x/24 + O(x**2) + \
        log(x)*x**2/2
    assert (s1 - s2).expand(force=True).removeO() == 0
    s1 = loggamma(1 / x).series(x)
    s2 = (1/x - Rational(1, 2))*log(1/x) - 1/x + log(2*pi)/2 + \
        x/12 - x**3/360 + x**5/1260 + O(x**7)
    assert ((s1 - s2).expand(force=True)).removeO() == 0

    assert loggamma(x).rewrite('intractable') == log(gamma(x))

    s1 = loggamma(x).series(x)
    assert s1 == -log(x) - EulerGamma*x + pi**2*x**2/12 + x**3*polygamma(2, 1)/6 + \
        pi**4*x**4/360 + x**5*polygamma(4, 1)/120 + O(x**6)
    assert s1 == loggamma(x).rewrite('intractable').series(x)

    assert conjugate(loggamma(x)) == loggamma(conjugate(x))
    assert conjugate(loggamma(0)) == conjugate(loggamma(0))
    assert conjugate(loggamma(1)) == loggamma(conjugate(1))
    assert conjugate(loggamma(-oo)) == conjugate(loggamma(-oo))
    assert loggamma(x).is_extended_real is None
    y = Symbol('y', nonnegative=True)
    assert loggamma(y).is_extended_real
    assert loggamma(w).is_extended_real is None

    def tN(N, M):
        assert loggamma(1 / x)._eval_nseries(x, n=N).getn() == M

    tN(0, 0)
    tN(1, 1)
    tN(2, 3)
    tN(3, 3)
    tN(4, 5)
    tN(5, 5)
Beispiel #25
0
import pytest

from diofant import (Add, E, Ei, EulerGamma, GoldenRatio, I, Integer, Li,
                     Limit, Mul, Pow, Rational, Symbol, acosh, acot, airyai,
                     airybi, atan, binomial, cbrt, cos, cosh, coth, digamma,
                     erf, exp, factorial, fibonacci, gamma, li, log, loggamma,
                     oo, pi, root, sign, sin, sinh, sqrt, tan, tanh, zeta)
from diofant.series.gruntz import compare
from diofant.series.gruntz import limitinf as gruntz
from diofant.series.gruntz import mrv, mrv_leadterm, rewrite
from diofant.series.gruntz import sign as mrv_sign


__all__ = ()

x = Symbol('x', real=True, positive=True)
m = Symbol('m', real=True, positive=True)


@pytest.mark.slow
def test_gruntz_evaluation():
    # Gruntz' thesis pp. 122 to 123
    # 8.1
    assert gruntz(exp(x)*(exp(1/x - exp(-x)) - exp(1/x)), x) == -1
    # 8.2
    assert gruntz(exp(x)*(exp(1/x + exp(-x) + exp(-x**2))
                          - exp(1/x - exp(-exp(x)))), x) == 1
    # 8.3
    assert gruntz(exp(exp(x - exp(-x))/(1 - 1/x)) - exp(exp(x)), x) == oo
    # 8.4
    assert gruntz(exp(exp(exp(x)/(1 - 1/x)))
Beispiel #26
0
def test_expressions_failing():
    n = Symbol('n', integer=True, positive=True)
    assert residue(exp(z)/(z - pi*I/4*a)**n, z, I*pi*a) == \
        exp(I*pi*a/4)/factorial(n - 1)
Beispiel #27
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def test_sympyissue_6843():
    n = Symbol('n', integer=True, positive=True)
    r = (n + 1)*(1 + 1/x)**(n + 1)/((1 + 1/x)**(n + 1) - 1) - (1 + 1/x)*x
    assert gruntz(r, x).simplify() == n/2
Beispiel #28
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def test_sympyissue_8853():
    p = Symbol('x', even=True, positive=True)
    assert floor(-p - Rational(1, 2)).is_even is False
    assert floor(-p + Rational(1, 2)).is_even
    assert ceiling(p - Rational(1, 2)).is_even
    assert ceiling(p + Rational(1, 2)).is_even is False
Beispiel #29
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def test_sympyissue_5084():
    x = Symbol('x')
    assert ((x + x * I) / (1 + I)).as_real_imag() == (re(
        (x + I * x) / (1 + I)), im((x + I * x) / (1 + I)))
Beispiel #30
0
                     cos, cosh, diff, erf, erfi, exp, expand_func, expand_mul,
                     factor, fresnels, gamma, im, integrate, log, lowergamma,
                     meijerg, nan, oo, pi, polar_lift, polygamma, re, sign,
                     simplify, sin, sinh, sqrt, sstr, symbols, sympify, tan,
                     tanh, trigsimp)
from diofant.abc import A, L, R, a, b, c, h, i, k, m, s, t, w, x, y, z
from diofant.functions.elementary.complexes import periodic_argument
from diofant.integrals.heurisch import heurisch
from diofant.integrals.risch import NonElementaryIntegral
from diofant.utilities.randtest import verify_numerically


__all__ = ()

x_1, x_2 = symbols('x_1 x_2')
n = Symbol('n', integer=True)
f = Function('f')


def diff_test(i):
    """Return the set of symbols, s, which were used in testing that
    i.diff(s) agrees with i.doit().diff(s). If there is an error then
    the assertion will fail, causing the test to fail.
    """
    syms = i.free_symbols
    for s in syms:
        assert (i.diff(s).doit() - i.doit().diff(s)).expand() == 0
    return syms


def test_improper_integral():
Beispiel #31
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def test_sympyissue_4680():
    N = Symbol('N')
    assert N.subs({N: 3}) == 3
Beispiel #32
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def test_sympyissue_4992():
    # Note: psi in _check_antecedents becomes NaN.
    a = Symbol('a', positive=True)
    assert simplify(expand_func(integrate(exp(-x)*log(x)*x**a, (x, 0, oo)))) == \
        (a*polygamma(0, a) + 1)*gamma(a)
Beispiel #33
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def test_sympyissue_4400():
    n = Symbol('n', integer=True, positive=True)
    assert integrate((x**n)*log(x), x) == \
        n*x*x**n*log(x)/(n**2 + 2*n + 1) + x*x**n*log(x)/(n**2 + 2*n + 1) - \
        x*x**n/(n**2 + 2*n + 1)
Beispiel #34
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def test_Dummy_from_Symbol():
    # should not get the full dictionary of assumptions
    n = Symbol('n', integer=True)
    d = n.as_dummy()
    assert repr(d) == "Dummy('n', integer=True)"