def test_rewrite():
assert besselj(n, z).rewrite(jn) == sqrt(2*z/pi)*jn(n - S.Half, z)
assert bessely(n, z).rewrite(yn) == sqrt(2*z/pi)*yn(n - S.Half, z)
assert besseli(n, z).rewrite(besselj) == \
exp(-I*n*pi/2)*besselj(n, polar_lift(I)*z)
assert besselj(n, z).rewrite(besseli) == \
exp(I*n*pi/2)*besseli(n, polar_lift(-I)*z)
nu = randcplx()
assert tn(besselj(nu, z), besselj(nu, z).rewrite(besseli), z)
assert tn(besselj(nu, z), besselj(nu, z).rewrite(bessely), z)
assert tn(besseli(nu, z), besseli(nu, z).rewrite(besselj), z)
assert tn(besseli(nu, z), besseli(nu, z).rewrite(bessely), z)
assert tn(bessely(nu, z), bessely(nu, z).rewrite(besselj), z)
assert tn(bessely(nu, z), bessely(nu, z).rewrite(besseli), z)
assert tn(besselk(nu, z), besselk(nu, z).rewrite(besselj), z)
assert tn(besselk(nu, z), besselk(nu, z).rewrite(besseli), z)
assert tn(besselk(nu, z), besselk(nu, z).rewrite(bessely), z)
# check that a rewrite was triggered, when the order is set to a generic
# symbol 'nu'
assert yn(nu, z) != yn(nu, z).rewrite(jn)
assert hn1(nu, z) != hn1(nu, z).rewrite(jn)
assert hn2(nu, z) != hn2(nu, z).rewrite(jn)
assert jn(nu, z) != jn(nu, z).rewrite(yn)
assert hn1(nu, z) != hn1(nu, z).rewrite(yn)
assert hn2(nu, z) != hn2(nu, z).rewrite(yn)
# rewriting spherical bessel functions (SBFs) w.r.t. besselj, bessely is
# not allowed if a generic symbol 'nu' is used as the order of the SBFs
# to avoid inconsistencies (the order of bessel[jy] is allowed to be
# complex-valued, whereas SBFs are defined only for integer orders)
order = nu
for f in (besselj, bessely):
assert hn1(order, z) == hn1(order, z).rewrite(f)
assert hn2(order, z) == hn2(order, z).rewrite(f)
assert jn(order, z).rewrite(besselj) == sqrt(2)*sqrt(pi)*sqrt(1/z)*besselj(order + S.Half, z)/2
assert jn(order, z).rewrite(bessely) == (-1)**nu*sqrt(2)*sqrt(pi)*sqrt(1/z)*bessely(-order - S.Half, z)/2
# for integral orders rewriting SBFs w.r.t bessel[jy] is allowed
N = Symbol('n', integer=True)
ri = randint(-11, 10)
for order in (ri, N):
for f in (besselj, bessely):
assert yn(order, z) != yn(order, z).rewrite(f)
assert jn(order, z) != jn(order, z).rewrite(f)
assert hn1(order, z) != hn1(order, z).rewrite(f)
assert hn2(order, z) != hn2(order, z).rewrite(f)
for func, refunc in product((yn, jn, hn1, hn2),
(jn, yn, besselj, bessely)):
assert tn(func(ri, z), func(ri, z).rewrite(refunc), z)
def test_yn():
z = symbols("z")
assert myn(0, z) == -cos(z)/z
assert myn(1, z) == -cos(z)/z**2 - sin(z)/z
assert myn(2, z) == -((3/z**3 - 1/z)*cos(z) + (3/z**2)*sin(z))
assert expand_func(yn(n, z)) == yn(n, z)
# SBFs not defined for complex-valued orders
assert yn(2+3j, 5.2+0.3j).evalf() == yn(2+3j, 5.2+0.3j)
assert eq([yn(2, 5.2+0.3j).evalf(10)],
[0.185250342 + 0.01489557397*I])
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'
def test_specfun():
n = Symbol('n')
for f in [besselj, bessely, besseli, besselk]:
assert julia_code(f(n, x)) == f.__name__ + '(n, x)'
for f in [airyai, airyaiprime, airybi, airybiprime]:
assert julia_code(f(x)) == f.__name__ + '(x)'
assert julia_code(hankel1(n, x)) == 'hankelh1(n, x)'
assert julia_code(hankel2(n, x)) == 'hankelh2(n, x)'
assert julia_code(jn(n, x)) == 'sqrt(2)*sqrt(pi)*sqrt(1./x).*besselj(n + 1/2, x)/2'
assert julia_code(yn(n, x)) == 'sqrt(2)*sqrt(pi)*sqrt(1./x).*bessely(n + 1/2, x)/2'
def test_specfun():
n = Symbol('n')
for f in [besselj, bessely, besseli, besselk]:
assert julia_code(f(n, x)) == f.__name__ + '(n, x)'
for f in [airyai, airyaiprime, airybi, airybiprime]:
assert julia_code(f(x)) == f.__name__ + '(x)'
assert julia_code(hankel1(n, x)) == 'hankelh1(n, x)'
assert julia_code(hankel2(n, x)) == 'hankelh2(n, x)'
assert julia_code(jn(n, x)) == 'sqrt(2)*sqrt(pi)*sqrt(1./x).*besselj(n + 1/2, x)/2'
assert julia_code(yn(n, x)) == 'sqrt(2)*sqrt(pi)*sqrt(1./x).*bessely(n + 1/2, x)/2'
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'
def test_specfun():
n = Symbol("n")
for f in [besselj, bessely, besseli, besselk]:
assert julia_code(f(n, x)) == f.__name__ + "(n, x)"
for f in [airyai, airyaiprime, airybi, airybiprime]:
assert julia_code(f(x)) == f.__name__ + "(x)"
assert julia_code(hankel1(n, x)) == "hankelh1(n, x)"
assert julia_code(hankel2(n, x)) == "hankelh2(n, x)"
assert julia_code(jn(
n, x)) == "sqrt(2)*sqrt(pi)*sqrt(1./x).*besselj(n + 1/2, x)/2"
assert julia_code(yn(
n, x)) == "sqrt(2)*sqrt(pi)*sqrt(1./x).*bessely(n + 1/2, x)/2"
def test_latex_bessel():
from sympy.functions.special.bessel import besselj, bessely, besseli, besselk, hankel1, hankel2, jn, yn
from sympy.abc import z
assert latex(besselj(n, z ** 2) ** k) == r"J^{k}_{n}\left(z^{2}\right)"
assert latex(bessely(n, z)) == r"Y_{n}\left(z\right)"
assert latex(besseli(n, z)) == r"I_{n}\left(z\right)"
assert latex(besselk(n, z)) == r"K_{n}\left(z\right)"
assert latex(hankel1(n, z ** 2) ** 2) == r"\left(H^{(1)}_{n}\left(z^{2}\right)\right)^{2}"
assert latex(hankel2(n, z)) == r"H^{(2)}_{n}\left(z\right)"
assert latex(jn(n, z)) == r"j_{n}\left(z\right)"
assert latex(yn(n, z)) == r"y_{n}\left(z\right)"
def test_latex_bessel():
from sympy.functions.special.bessel import (besselj, bessely, besseli,
besselk, hankel1, hankel2, jn, yn)
from sympy.abc import z
assert latex(besselj(n, z**2)**k) == r'J^{k}_{n}\left(z^{2}\right)'
assert latex(bessely(n, z)) == r'Y_{n}\left(z\right)'
assert latex(besseli(n, z)) == r'I_{n}\left(z\right)'
assert latex(besselk(n, z)) == r'K_{n}\left(z\right)'
assert latex(hankel1(n, z**2)**2) == \
r'\left(H^{(1)}_{n}\left(z^{2}\right)\right)^{2}'
assert latex(hankel2(n, z)) == r'H^{(2)}_{n}\left(z\right)'
assert latex(jn(n, z)) == r'j_{n}\left(z\right)'
assert latex(yn(n, z)) == r'y_{n}\left(z\right)'
def test_latex_bessel():
from sympy.functions.special.bessel import (besselj, bessely, besseli,
besselk, hankel1, hankel2, jn, yn)
from sympy.abc import z
assert latex(besselj(n, z**2)**k) == r'J^{k}_{n}\left(z^{2}\right)'
assert latex(bessely(n, z)) == r'Y_{n}\left(z\right)'
assert latex(besseli(n, z)) == r'I_{n}\left(z\right)'
assert latex(besselk(n, z)) == r'K_{n}\left(z\right)'
assert latex(hankel1(n, z**2)**2) == \
r'\left(H^{(1)}_{n}\left(z^{2}\right)\right)^{2}'
assert latex(hankel2(n, z)) == r'H^{(2)}_{n}\left(z\right)'
assert latex(jn(n, z)) == r'j_{n}\left(z\right)'
assert latex(yn(n, z)) == r'y_{n}\left(z\right)'
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'
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)'
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)'
def test_meromorphic():
assert besselj(2, x).is_meromorphic(x, 1) == True
assert besselj(2, x).is_meromorphic(x, 0) == True
assert besselj(2, x).is_meromorphic(x, oo) == False
assert besselj(S(2)/3, x).is_meromorphic(x, 1) == True
assert besselj(S(2)/3, x).is_meromorphic(x, 0) == False
assert besselj(S(2)/3, x).is_meromorphic(x, oo) == False
assert besselj(x, 2*x).is_meromorphic(x, 2) == False
assert besselk(0, x).is_meromorphic(x, 1) == True
assert besselk(2, x).is_meromorphic(x, 0) == True
assert besseli(0, x).is_meromorphic(x, 1) == True
assert besseli(2, x).is_meromorphic(x, 0) == True
assert bessely(0, x).is_meromorphic(x, 1) == True
assert bessely(0, x).is_meromorphic(x, 0) == False
assert bessely(2, x).is_meromorphic(x, 0) == True
assert hankel1(3, x**2 + 2*x).is_meromorphic(x, 1) == True
assert hankel1(0, x).is_meromorphic(x, 0) == False
assert hankel2(11, 4).is_meromorphic(x, 5) == True
assert hn1(6, 7*x**3 + 4).is_meromorphic(x, 7) == True
assert hn2(3, 2*x).is_meromorphic(x, 9) == True
assert jn(5, 2*x + 7).is_meromorphic(x, 4) == True
assert yn(8, x**2 + 11).is_meromorphic(x, 6) == True
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)"
def test_sympy__functions__special__bessel__yn():
from sympy.functions.special.bessel import yn
assert _test_args(yn(0, x))
def myn(n, z):
return expand_func(yn(n, z))
def test_sympy__functions__special__bessel__yn():
from sympy.functions.special.bessel import yn
assert _test_args(yn(0, x))
