Пример #1
0
def test_airyaiprime():
    z = Symbol('z', real=False)
    t = Symbol('t', negative=True)
    p = Symbol('p', positive=True)

    assert isinstance(airyaiprime(z), airyaiprime)

    assert airyaiprime(0) == -3**Rational(2, 3)/(3*gamma(Rational(1, 3)))
    assert airyaiprime(oo) == 0

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

    assert series(airyaiprime(z), z, 0, 3) == (
        -3**Rational(2, 3)/(3*gamma(Rational(1, 3))) + 3**Rational(1, 3)*z**2/(6*gamma(Rational(2, 3))) + O(z**3))

    assert airyaiprime(z).rewrite(hyper) == (
        3**Rational(1, 3)*z**2*hyper((), (Rational(5, 3),), z**3/9)/(6*gamma(Rational(2, 3))) -
        3**Rational(2, 3)*hyper((), (Rational(1, 3),), z**3/9)/(3*gamma(Rational(1, 3))))

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

    assert expand_func(airyaiprime(2*(3*z**5)**Rational(1, 3))) == (
        sqrt(3)*(z**Rational(5, 3)/(z**5)**Rational(1, 3) - 1)*airybiprime(2*3**Rational(1, 3)*z**Rational(5, 3))/6 +
        (z**Rational(5, 3)/(z**5)**Rational(1, 3) + 1)*airyaiprime(2*3**Rational(1, 3)*z**Rational(5, 3))/2)
Пример #2
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def test_airybi():
    z = Symbol('z', real=False)
    t = Symbol('t', negative=True)
    p = Symbol('p', positive=True)

    assert isinstance(airybi(z), airybi)

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

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

    assert series(airybi(z), z, 0, 3) == (
        3**(S(1)/3)*gamma(S(1)/3)/(2*pi) + 3**(S(2)/3)*z*gamma(S(2)/3)/(2*pi) + O(z**3))

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

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

    assert expand_func(airybi(2*(3*z**5)**(S(1)/3))) == (
        sqrt(3)*(1 - (z**5)**(S(1)/3)/z**(S(5)/3))*airyai(2*3**(S(1)/3)*z**(S(5)/3))/2 +
        (1 + (z**5)**(S(1)/3)/z**(S(5)/3))*airybi(2*3**(S(1)/3)*z**(S(5)/3))/2)
Пример #3
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def test_airybi():
    z = Symbol('z', 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) is oo
    assert airybi(-oo) == 0

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

    assert series(airybi(z), z, 0, 3) == (
        3**Rational(1, 3)*gamma(Rational(1, 3))/(2*pi) + 3**Rational(2, 3)*z*gamma(Rational(2, 3))/(2*pi) + O(z**3))

    assert airybi(z).rewrite(hyper) == (
        3**Rational(1, 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 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 airybi(z).rewrite(besseli) == (
        sqrt(3)*(z*besseli(Rational(1, 3), 2*z**Rational(3, 2)/3)/(z**Rational(3, 2))**Rational(1, 3) +
                 (z**Rational(3, 2))**Rational(1, 3)*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 expand_func(airybi(2*(3*z**5)**Rational(1, 3))) == (
        sqrt(3)*(1 - (z**5)**Rational(1, 3)/z**Rational(5, 3))*airyai(2*3**Rational(1, 3)*z**Rational(5, 3))/2 +
        (1 + (z**5)**Rational(1, 3)/z**Rational(5, 3))*airybi(2*3**Rational(1, 3)*z**Rational(5, 3))/2)
Пример #4
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def test_airyaiprime():
    z = Symbol('z', real=False)
    t = Symbol('t', negative=True)
    p = Symbol('p', positive=True)

    assert isinstance(airyaiprime(z), airyaiprime)

    assert airyaiprime(0) == -3**(S(2)/3)/(3*gamma(S(1)/3))
    assert airyaiprime(oo) == 0

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

    assert series(airyaiprime(z), z, 0, 3) == (
        -3**(S(2)/3)/(3*gamma(S(1)/3)) + 3**(S(1)/3)*z**2/(6*gamma(S(2)/3)) + O(z**3))

    assert airyaiprime(z).rewrite(hyper) == (
        3**(S(1)/3)*z**2*hyper((), (S(5)/3,), z**S(3)/9)/(6*gamma(S(2)/3)) -
        3**(S(2)/3)*hyper((), (S(1)/3,), z**S(3)/9)/(3*gamma(S(1)/3)))

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

    assert expand_func(airyaiprime(2*(3*z**5)**(S(1)/3))) == (
        sqrt(3)*(z**(S(5)/3)/(z**5)**(S(1)/3) - 1)*airybiprime(2*3**(S(1)/3)*z**(S(5)/3))/6 +
        (z**(S(5)/3)/(z**5)**(S(1)/3) + 1)*airyaiprime(2*3**(S(1)/3)*z**(S(5)/3))/2)
Пример #5
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def test_airybiprime():
    z = Symbol('z', real=False)
    t = Symbol('t', negative=True)
    p = Symbol('p', positive=True)

    assert isinstance(airybiprime(z), airybiprime)

    assert airybiprime(0) == 3**(S(1)/6)/gamma(S(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) == (
        3**(S(1)/6)/gamma(S(1)/3) + 3**(S(5)/6)*z**2/(6*gamma(S(2)/3)) + O(z**3))

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

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

    assert expand_func(airybiprime(2*(3*z**5)**(S(1)/3))) == (
        sqrt(3)*(z**(S(5)/3)/(z**5)**(S(1)/3) - 1)*airyaiprime(2*3**(S(1)/3)*z**(S(5)/3))/2 +
        (z**(S(5)/3)/(z**5)**(S(1)/3) + 1)*airybiprime(2*3**(S(1)/3)*z**(S(5)/3))/2)
Пример #6
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def test_specfun():
    n = Symbol('n')
    for f in [besselj, bessely, besseli, besselk]:
        assert octave_code(f(n, x)) == f.__name__ + '(n, x)'
    for f in (erfc, erfi, erf, erfinv, erfcinv, fresnelc, fresnels, gamma):
        assert octave_code(f(x)) == f.__name__ + '(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\').*gamma(n))'
    assert octave_code(lowergamma(n, x)) == '(gammainc(x, n).*gamma(n))'
    assert octave_code(z**lowergamma(n, x)) == 'z.^(gammainc(x, n).*gamma(n))'
    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(LambertW(x)) == 'lambertw(x)'
    assert octave_code(LambertW(x, n)) == 'lambertw(n, x)'

    # Automatic rewrite
    assert octave_code(Ei(x)) == 'logint(exp(x))'
    assert octave_code(dirichlet_eta(x)) == '(1 - 2.^(1 - x)).*zeta(x)'
    assert octave_code(
        riemann_xi(x)) == 'pi.^(-x/2).*x.*(x - 1).*gamma(x/2).*zeta(x)/2'
Пример #7
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def test_airy_base():
    z = Symbol('z')
    x = Symbol('x', real=True)
    y = Symbol('y', real=True)

    assert conjugate(airyai(z)) == airyai(conjugate(z))
    assert airyai(x).is_extended_real

    assert airyai(x + I * y).as_real_imag() == (
        airyai(x - I * y) / 2 + airyai(x + I * y) / 2,
        I * (airyai(x - I * y) - airyai(x + I * y)) / 2)
Пример #8
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def test_airy_base():
    z = Symbol('z')
    x = Symbol('x', real=True)
    y = Symbol('y', real=True)

    assert conjugate(airyai(z)) == airyai(conjugate(z))
    assert airyai(x).is_real

    assert airyai(x+I*y).as_real_imag() == (
        airyai(x - I*x*Abs(y)/Abs(x))/2 + airyai(x + I*x*Abs(y)/Abs(x))/2,
        I*x*(airyai(x - I*x*Abs(y)/Abs(x)) -
             airyai(x + I*x*Abs(y)/Abs(x)))*Abs(y)/(2*y*Abs(x)))
Пример #9
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def test_airy_base():
    z = Symbol('z')
    x = Symbol('x', real=True)
    y = Symbol('y', real=True)

    assert conjugate(airyai(z)) == airyai(conjugate(z))
    assert airyai(x).is_real

    assert airyai(x+I*y).as_real_imag() == (
        airyai(x - I*x*Abs(y)/Abs(x))/2 + airyai(x + I*x*Abs(y)/Abs(x))/2,
        I*x*(airyai(x - I*x*Abs(y)/Abs(x)) -
             airyai(x + I*x*Abs(y)/Abs(x)))*Abs(y)/(2*y*Abs(x)))
Пример #10
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def test_specfun():
    n = Symbol('n')
    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(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'
Пример #11
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def test_specfun():
    n = Symbol('n')
    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'
Пример #12
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def test_specfun():
    n = Symbol('n')
    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(LambertW(x)) == 'lambertw(x)'
    assert octave_code(LambertW(x, n)) == 'lambertw(n, x)'
Пример #13
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def test_airy():
    from sympy.functions.special.bessel import (airyai, airybi)

    expr1 = airyai(x)
    expr2 = airybi(x)

    prntr = SciPyPrinter()
    assert prntr.doprint(expr1) == 'scipy.special.airy(x)[0]'
    assert prntr.doprint(expr2) == 'scipy.special.airy(x)[2]'

    prntr = NumPyPrinter()
    assert "Not supported" in prntr.doprint(expr1)
    assert "Not supported" in prntr.doprint(expr2)

    prntr = PythonCodePrinter()
    assert "Not supported" in prntr.doprint(expr1)
    assert "Not supported" in prntr.doprint(expr2)
Пример #14
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def test_fps__hyper():
    f = sin(x)
    assert fps(f, x).truncate() == x - x**3/6 + x**5/120 + O(x**6)

    f = cos(x)
    assert fps(f, x).truncate() == 1 - x**2/2 + x**4/24 + O(x**6)

    f = exp(x)
    assert fps(f, x).truncate() == \
        1 + x + x**2/2 + x**3/6 + x**4/24 + x**5/120 + O(x**6)

    f = atan(x)
    assert fps(f, x).truncate() == x - x**3/3 + x**5/5 + O(x**6)

    f = exp(acos(x))
    assert fps(f, x).truncate() == \
        (exp(pi/2) - x*exp(pi/2) + x**2*exp(pi/2)/2 - x**3*exp(pi/2)/3 +
         5*x**4*exp(pi/2)/24 - x**5*exp(pi/2)/6 + O(x**6))

    f = exp(acosh(x))
    assert fps(f, x).truncate() == I + x - I*x**2/2 - I*x**4/8 + O(x**6)

    f = atan(1/x)
    assert fps(f, x).truncate() == pi/2 - x + x**3/3 - x**5/5 + O(x**6)

    f = x*atan(x) - log(1 + x**2) / 2
    assert fps(f, x, rational=False).truncate() == x**2/2 - x**4/12 + O(x**6)

    f = log(1 + x)
    assert fps(f, x, rational=False).truncate() == \
        x - x**2/2 + x**3/3 - x**4/4 + x**5/5 + O(x**6)

    f = airyai(x**2)
    assert fps(f, x).truncate() == \
        (3**Rational(5, 6)*gamma(Rational(1, 3))/(6*pi) -
         3**Rational(2, 3)*x**2/(3*gamma(Rational(1, 3))) + O(x**6))

    f = exp(x)*sin(x)
    assert fps(f, x).truncate() == x + x**2 + x**3/3 - x**5/30 + O(x**6)

    f = exp(x)*sin(x)/x
    assert fps(f, x).truncate() == 1 + x + x**2/3 - x**4/30 - x**5/90 + O(x**6)

    f = sin(x) * cos(x)
    assert fps(f, x).truncate() == x - 2*x**3/3 + 2*x**5/15 + O(x**6)
Пример #15
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def test_specfun():
    n = Symbol('n')
    for f in [besselj, bessely, besseli, besselk]:
        assert octave_code(f(n, x)) == f.__name__ + '(n, x)'
    for f in (erfc, erfi, erf, erfinv, erfcinv, fresnelc, fresnels, gamma):
        assert octave_code(f(x)) == f.__name__ + '(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\').*gamma(n))'
    assert octave_code(lowergamma(n, x)) == '(gammainc(x, n).*gamma(n))'
    assert octave_code(z**lowergamma(n, x)) == 'z.^(gammainc(x, n).*gamma(n))'
    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(LambertW(x)) == 'lambertw(x)'
    assert octave_code(LambertW(x, n)) == 'lambertw(n, x)'
Пример #16
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def test_specfun():
    n = Symbol("n")
    for f in [besselj, bessely, besseli, besselk]:
        assert octave_code(f(n, x)) == f.__name__ + "(n, x)"
    for f in (erfc, erfi, erf, erfinv, erfcinv, fresnelc, fresnels, gamma):
        assert octave_code(f(x)) == f.__name__ + "(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').*gamma(n))"
    assert octave_code(lowergamma(n, x)) == "(gammainc(x, n).*gamma(n))"
    assert octave_code(z**lowergamma(n, x)) == "z.^(gammainc(x, n).*gamma(n))"
    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(LambertW(x)) == "lambertw(x)"
    assert octave_code(LambertW(x, n)) == "lambertw(n, x)"
Пример #17
0
def test_simpleDE():
    # Tests just the first valid DE
    for DE in simpleDE(exp(x), x, f):
        assert DE == (-f(x) + Derivative(f(x), x), 1)
        break
    for DE in simpleDE(sin(x), x, f):
        assert DE == (f(x) + Derivative(f(x), x, x), 2)
        break
    for DE in simpleDE(log(1 + x), x, f):
        assert DE == ((x + 1)*Derivative(f(x), x, 2) + Derivative(f(x), x), 2)
        break
    for DE in simpleDE(asin(x), x, f):
        assert DE == (x*Derivative(f(x), x) + (x**2 - 1)*Derivative(f(x), x, x),
                      2)
        break
    for DE in simpleDE(exp(x)*sin(x), x, f):
        assert DE == (2*f(x) - 2*Derivative(f(x)) + Derivative(f(x), x, x), 2)
        break
    for DE in simpleDE(((1 + x)/(1 - x))**n, x, f):
        assert DE == (2*n*f(x) + (x**2 - 1)*Derivative(f(x), x), 1)
        break
    for DE in simpleDE(airyai(x), x, f):
        assert DE == (-x*f(x) + Derivative(f(x), x, x), 2)
        break
Пример #18
0
def test_airyai():
    z = Symbol('z', real=False)
    t = Symbol('t', negative=True)
    p = Symbol('p', positive=True)

    assert isinstance(airyai(z), airyai)

    assert airyai(0) == 3**(S(1)/3)/(3*gamma(S(2)/3))
    assert airyai(oo) == 0
    assert airyai(-oo) == 0

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

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

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

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

    assert expand_func(airyai(2*(3*z**5)**(S(1)/3))) == (
        -sqrt(3)*(-1 + (z**5)**(S(1)/3)/z**(S(5)/3))*airybi(2*3**(S(1)/3)*z**(S(5)/3))/6 +
         (1 + (z**5)**(S(1)/3)/z**(S(5)/3))*airyai(2*3**(S(1)/3)*z**(S(5)/3))/2)