Beispiel #1
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def test_intractable():
    assert limit(1/gamma(x), x, oo) == 0
    assert limit(1/loggamma(x), x, oo) == 0
    assert limit(gamma(x)/loggamma(x), x, oo) == oo
    assert limit(exp(gamma(x))/gamma(x), x, oo) == oo
    assert limit(gamma(3 + 1/x), x, oo) == 2
    assert limit(gamma(Rational(1, 7) + 1/x), x, oo) == gamma(Rational(1, 7))
    assert limit(log(x**x)/log(gamma(x)), x, oo) == 1
    assert limit(log(gamma(gamma(x)))/exp(x), x, oo) == oo
    assert limit(acosh(1 + 1/x)*sqrt(x), x, oo) == sqrt(2)

    # issue sympy/sympy#10804
    assert limit(2*airyai(x)*root(x, 4) *
                 exp(2*x**Rational(3, 2)/3), x, oo) == 1/sqrt(pi)
    assert limit(airybi(x)*root(x, 4) *
                 exp(-2*x**Rational(3, 2)/3), x, oo) == 1/sqrt(pi)
    assert limit(airyai(1/x), x, oo) == (3**Rational(5, 6) *
                                         gamma(Rational(1, 3))/(6*pi))
    assert limit(airybi(1/x), x, oo) == cbrt(3)*gamma(Rational(1, 3))/(2*pi)
    assert limit(airyai(2 + 1/x), x, oo) == airyai(2)
    assert limit(airybi(2 + 1/x), x, oo) == airybi(2)

    # issue sympy/sympy#10976
    assert limit(erf(m/x)/erf(1/x), x, oo) == m

    assert limit(Max(x**2, x, exp(x))/x, x, oo) == oo
Beispiel #2
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def test_specfun():
    for f in [besselj, bessely, besseli, besselk]:
        assert octave_code(f(n, x)) == f.__name__ + '(n, x)'
    assert octave_code(hankel1(n, x)) == 'besselh(n, 1, x)'
    assert octave_code(hankel2(n, x)) == 'besselh(n, 2, x)'
    assert octave_code(airyai(x)) == 'airy(0, x)'
    assert octave_code(airyaiprime(x)) == 'airy(1, x)'
    assert octave_code(airybi(x)) == 'airy(2, x)'
    assert octave_code(airybiprime(x)) == 'airy(3, x)'
    assert octave_code(uppergamma(n, x)) == "gammainc(x, n, 'upper')"
    assert octave_code(lowergamma(n, x)) == "gammainc(x, n, 'lower')"
    assert octave_code(jn(
        n, x)) == 'sqrt(2)*sqrt(pi)*sqrt(1./x).*besselj(n + 1/2, x)/2'
    assert octave_code(yn(
        n, x)) == 'sqrt(2)*sqrt(pi)*sqrt(1./x).*bessely(n + 1/2, x)/2'
    assert octave_code(Chi(x)) == 'coshint(x)'
    assert octave_code(Ci(x)) == 'cosint(x)'
    assert octave_code(laguerre(n, x)) == 'laguerreL(n, x)'
    assert octave_code(li(x)) == 'logint(x)'
    assert octave_code(loggamma(x)) == 'gammaln(x)'
    assert octave_code(polygamma(n, x)) == 'psi(n, x)'
    assert octave_code(Shi(x)) == 'sinhint(x)'
    assert octave_code(Si(x)) == 'sinint(x)'
    assert octave_code(LambertW(x)) == 'lambertw(x)'
    assert octave_code(LambertW(x, n)) == 'lambertw(n, x)'
    assert octave_code(zeta(x)) == 'zeta(x)'
    assert octave_code(zeta(
        x, y)) == '% Not supported in Octave:\n% zeta\nzeta(x, y)'
Beispiel #3
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def test_intractable():
    assert gruntz(1/gamma(x), x) == 0
    assert gruntz(1/loggamma(x), x) == 0
    assert gruntz(gamma(x)/loggamma(x), x) == oo
    assert gruntz(exp(gamma(x))/gamma(x), x) == oo
    assert gruntz(gamma(3 + 1/x), x) == 2
    assert gruntz(gamma(Rational(1, 7) + 1/x), x) == gamma(Rational(1, 7))
    assert gruntz(log(x**x)/log(gamma(x)), x) == 1
    assert gruntz(log(gamma(gamma(x)))/exp(x), x) == oo

    # issue sympy/sympy#10804
    assert gruntz(2*airyai(x)*root(x, 4) *
                  exp(2*x**Rational(3, 2)/3), x) == 1/sqrt(pi)
    assert gruntz(airybi(x)*root(x, 4) *
                  exp(-2*x**Rational(3, 2)/3), x) == 1/sqrt(pi)
    assert gruntz(airyai(1/x), x) == (3**Rational(5, 6) *
                                      gamma(Rational(1, 3))/(6*pi))
    assert gruntz(airybi(1/x), x) == cbrt(3)*gamma(Rational(1, 3))/(2*pi)
    assert gruntz(airyai(2 + 1/x), x) == airyai(2)
    assert gruntz(airybi(2 + 1/x), x) == airybi(2)
Beispiel #4
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def test_intractable():
    assert gruntz(1/gamma(x), x) == 0
    assert gruntz(1/loggamma(x), x) == 0
    assert gruntz(gamma(x)/loggamma(x), x) == oo
    assert gruntz(exp(gamma(x))/gamma(x), x) == oo
    assert gruntz(gamma(3 + 1/x), x) == 2
    assert gruntz(gamma(Rational(1, 7) + 1/x), x) == gamma(Rational(1, 7))
    assert gruntz(log(x**x)/log(gamma(x)), x) == 1
    assert gruntz(log(gamma(gamma(x)))/exp(x), x) == oo

    # issue sympy/sympy#10804
    assert gruntz(2*airyai(x)*root(x, 4) *
                  exp(2*x**Rational(3, 2)/3), x) == 1/sqrt(pi)
    assert gruntz(airybi(x)*root(x, 4) *
                  exp(-2*x**Rational(3, 2)/3), x) == 1/sqrt(pi)
    assert gruntz(airyai(1/x), x) == (3**Rational(5, 6) *
                                      gamma(Rational(1, 3))/(6*pi))
    assert gruntz(airybi(1/x), x) == cbrt(3)*gamma(Rational(1, 3))/(2*pi)
    assert gruntz(airyai(2 + 1/x), x) == airyai(2)
    assert gruntz(airybi(2 + 1/x), x) == airybi(2)
Beispiel #5
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def test_airyai():
    z = Symbol('z', extended_real=False)
    r = Symbol('r', extended_real=True)
    t = Symbol('t', negative=True)
    p = Symbol('p', positive=True)

    assert isinstance(airyai(z), airyai)

    assert airyai(0) == cbrt(3)/(3*gamma(Rational(2, 3)))
    assert airyai(oo) == 0
    assert airyai(-oo) == 0

    assert diff(airyai(z), z) == airyaiprime(z)

    assert airyai(z).series(z, 0, 3) == (
        3**Rational(5, 6)*gamma(Rational(1, 3))/(6*pi) - root(3, 6)*z*gamma(Rational(2, 3))/(2*pi) + O(z**3))

    l = Limit(airyai(I/x)/(exp(-Rational(2, 3)*(I/x)**Rational(3, 2))*sqrt(pi*sqrt(I/x))/2), x, 0)
    assert l.doit() == l  # cover _airyais._eval_aseries

    assert airyai(z).rewrite(hyper) == (
        -3**Rational(2, 3)*z*hyper((), (Rational(4, 3),), z**3/9)/(3*gamma(Rational(1, 3))) +
        cbrt(3)*hyper((), (Rational(2, 3),), z**3/9)/(3*gamma(Rational(2, 3))))

    assert isinstance(airyai(z).rewrite(besselj), airyai)
    assert airyai(t).rewrite(besselj) == (
        sqrt(-t)*(besselj(-Rational(1, 3), 2*(-t)**Rational(3, 2)/3) +
                  besselj(Rational(1, 3), 2*(-t)**Rational(3, 2)/3))/3)
    assert airyai(z).rewrite(besseli) == (
        -z*besseli(Rational(1, 3), 2*z**Rational(3, 2)/3)/(3*cbrt(z**Rational(3, 2))) +
        cbrt(z**Rational(3, 2))*besseli(-Rational(1, 3), 2*z**Rational(3, 2)/3)/3)
    assert airyai(p).rewrite(besseli) == (
        sqrt(p)*(besseli(-Rational(1, 3), 2*p**Rational(3, 2)/3) -
                 besseli(Rational(1, 3), 2*p**Rational(3, 2)/3))/3)

    assert expand_func(airyai(2*cbrt(3*z**5))) == (
        -sqrt(3)*(-1 + cbrt(z**5)/z**Rational(5, 3))*airybi(2*cbrt(3)*z**Rational(5, 3))/6 +
        (1 + cbrt(z**5)/z**Rational(5, 3))*airyai(2*cbrt(3)*z**Rational(5, 3))/2)
    assert expand_func(airyai(x*y)) == airyai(x*y)
    assert expand_func(airyai(log(x))) == airyai(log(x))
    assert expand_func(airyai(2*root(3*z**5, 5))) == airyai(2*root(3*z**5, 5))

    assert (airyai(r).as_real_imag() ==
            airyai(r).as_real_imag(deep=False) == (airyai(r), 0))
    assert airyai(x).as_real_imag() == airyai(x).as_real_imag(deep=False)
    assert (airyai(x).as_real_imag() ==
            (airyai(re(x) - I*re(x)*abs(im(x))/abs(re(x)))/2 +
             airyai(re(x) + I*re(x)*abs(im(x))/abs(re(x)))/2,
             I*(airyai(re(x) - I*re(x)*abs(im(x))/abs(re(x))) -
                airyai(re(x) + I*re(x)*abs(im(x))/abs(re(x)))) *
             re(x)*abs(im(x))/(2*im(x)*abs(re(x)))))

    assert airyai(x).taylor_term(-1, x) == 0
Beispiel #6
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def test_airybiprime():
    z = Symbol('z', extended_real=False)
    t = Symbol('t', negative=True)
    p = Symbol('p', positive=True)

    assert isinstance(airybiprime(z), airybiprime)

    assert airybiprime(0) == root(3, 6) / gamma(Rational(1, 3))
    assert airybiprime(oo) == oo
    assert airybiprime(-oo) == 0

    assert diff(airybiprime(z), z) == z * airybi(z)

    assert series(airybiprime(z), z, 0,
                  3) == (root(3, 6) / gamma(Rational(1, 3)) +
                         3**Rational(5, 6) * z**2 /
                         (6 * gamma(Rational(2, 3))) + O(z**3))

    assert airybiprime(z).rewrite(hyper) == (
        3**Rational(5, 6) * z**2 * hyper((), (Rational(5, 3), ), z**3 / 9) /
        (6 * gamma(Rational(2, 3))) + root(3, 6) * hyper(
            (), (Rational(1, 3), ), z**3 / 9) / gamma(Rational(1, 3)))

    assert isinstance(airybiprime(z).rewrite(besselj), airybiprime)
    assert (airybiprime(t).rewrite(besselj) == -sqrt(3) * t *
            (besselj(-Rational(2, 3), 2 * (-t)**Rational(3, 2) / 3) +
             besselj(Rational(2, 3), 2 * (-t)**Rational(3, 2) / 3)) / 3)
    assert airybiprime(z).rewrite(besseli) == (
        sqrt(3) * (z**2 * besseli(Rational(2, 3), 2 * z**Rational(3, 2) / 3) /
                   (z**Rational(3, 2))**Rational(2, 3) +
                   (z**Rational(3, 2))**Rational(2, 3) *
                   besseli(-Rational(2, 3), 2 * z**Rational(3, 2) / 3)) / 3)
    assert airybiprime(p).rewrite(besseli) == (
        sqrt(3) * p * (besseli(-Rational(2, 3), 2 * p**Rational(3, 2) / 3) +
                       besseli(Rational(2, 3), 2 * p**Rational(3, 2) / 3)) / 3)
    assert airybiprime(p).rewrite(besselj) == airybiprime(p)

    assert expand_func(airybiprime(
        2 *
        cbrt(3 * z**5))) == (sqrt(3) * (z**Rational(5, 3) / cbrt(z**5) - 1) *
                             airyaiprime(2 * cbrt(3) * z**Rational(5, 3)) / 2 +
                             (z**Rational(5, 3) / cbrt(z**5) + 1) *
                             airybiprime(2 * cbrt(3) * z**Rational(5, 3)) / 2)
    assert expand_func(airybiprime(x * y)) == airybiprime(x * y)
    assert expand_func(airybiprime(log(x))) == airybiprime(log(x))
    assert expand_func(airybiprime(2 * root(3 * z**5, 5))) == airybiprime(
        2 * root(3 * z**5, 5))

    assert airybiprime(-2).evalf(50) == Float(
        '0.27879516692116952268509756941098324140300059345163131', dps=50)
Beispiel #7
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def test_diff():
    assert besselj(n, z).diff(z) == besselj(n - 1, z)/2 - besselj(n + 1, z)/2
    assert bessely(n, z).diff(z) == bessely(n - 1, z)/2 - bessely(n + 1, z)/2
    assert besseli(n, z).diff(z) == besseli(n - 1, z)/2 + besseli(n + 1, z)/2
    assert besselk(n, z).diff(z) == -besselk(n - 1, z)/2 - besselk(n + 1, z)/2
    assert hankel1(n, z).diff(z) == hankel1(n - 1, z)/2 - hankel1(n + 1, z)/2
    assert hankel2(n, z).diff(z) == hankel2(n - 1, z)/2 - hankel2(n + 1, z)/2

    pytest.raises(ArgumentIndexError, lambda: besselj(n, z).fdiff(3))
    pytest.raises(ArgumentIndexError, lambda: jn(n, z).fdiff(3))
    pytest.raises(ArgumentIndexError, lambda: airyai(z).fdiff(2))
    pytest.raises(ArgumentIndexError, lambda: airybi(z).fdiff(2))
    pytest.raises(ArgumentIndexError, lambda: airyaiprime(z).fdiff(2))
    pytest.raises(ArgumentIndexError, lambda: airybiprime(z).fdiff(2))
Beispiel #8
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def test_airybi():
    z = Symbol('z', extended_real=False)
    t = Symbol('t', negative=True)
    p = Symbol('p', positive=True)

    assert isinstance(airybi(z), airybi)

    assert airybi(0) == 3**Rational(5, 6) / (3 * gamma(Rational(2, 3)))
    assert airybi(oo) == oo
    assert airybi(-oo) == 0

    assert diff(airybi(z), z) == airybiprime(z)

    assert series(airybi(z), z, 0,
                  3) == (cbrt(3) * gamma(Rational(1, 3)) / (2 * pi) +
                         3**Rational(2, 3) * z * gamma(Rational(2, 3)) /
                         (2 * pi) + O(z**3))
    l = Limit(
        airybi(I / x) /
        (exp(Rational(2, 3) *
             (I / x)**Rational(3, 2)) * sqrt(pi * sqrt(I / x))), x, 0)
    assert l.doit() == l

    assert airybi(z).rewrite(hyper) == (root(3, 6) * z * hyper(
        (), (Rational(4, 3), ), z**3 / 9) / gamma(Rational(1, 3)) +
                                        3**Rational(5, 6) * hyper(
                                            (), (Rational(2, 3), ), z**3 / 9) /
                                        (3 * gamma(Rational(2, 3))))

    assert isinstance(airybi(z).rewrite(besselj), airybi)
    assert (airybi(t).rewrite(besselj) == sqrt(3) * sqrt(-t) *
            (besselj(-1 / 3, 2 * (-t)**Rational(3, 2) / 3) -
             besselj(Rational(1, 3), 2 * (-t)**Rational(3, 2) / 3)) / 3)
    assert airybi(z).rewrite(besseli) == (
        sqrt(3) * (z * besseli(Rational(1, 3), 2 * z**Rational(3, 2) / 3) /
                   cbrt(z**Rational(3, 2)) + cbrt(z**Rational(3, 2)) *
                   besseli(-Rational(1, 3), 2 * z**Rational(3, 2) / 3)) / 3)
    assert airybi(p).rewrite(besseli) == (
        sqrt(3) * sqrt(p) *
        (besseli(-Rational(1, 3), 2 * p**Rational(3, 2) / 3) +
         besseli(Rational(1, 3), 2 * p**Rational(3, 2) / 3)) / 3)
    assert airybi(p).rewrite(besselj) == airybi(p)

    assert expand_func(airybi(
        2 *
        cbrt(3 * z**5))) == (sqrt(3) * (1 - cbrt(z**5) / z**Rational(5, 3)) *
                             airyai(2 * cbrt(3) * z**Rational(5, 3)) / 2 +
                             (1 + cbrt(z**5) / z**Rational(5, 3)) *
                             airybi(2 * cbrt(3) * z**Rational(5, 3)) / 2)
    assert expand_func(airybi(x * y)) == airybi(x * y)
    assert expand_func(airybi(log(x))) == airybi(log(x))
    assert expand_func(airybi(2 * root(3 * z**5, 5))) == airybi(
        2 * root(3 * z**5, 5))

    assert airybi(x).taylor_term(-1, x) == 0