def test_singularities_ks_raises_NotImplementedError():
"""
Tests, if a NotImplementedError is raised, when KerrSchild coordinates \
are used with ``singularities()``
"""
mk = Kerr(coords="KS", M=1e22, a=0.5)
try:
mk_sing = mk.singularities()
assert False
except NotImplementedError:
assert True
def test_singularities_for_uncharged_nonrotating_case():
"""
Tests, if all metric singularities match up across Schwarzschild, Kerr & Kerr-Newman \
spacetimes, when a -> 0 & Q -> 0, subject to choice to coordinates (here, Spherical and BL)
"""
theta = np.pi / 4
M, a, Q = 5e27, 0., 0.
ms = Schwarzschild(M=M)
mk = Kerr(coords="BL", M=M, a=a)
mkn = KerrNewman(coords="BL", M=M, a=a, Q=Q)
mssing = ms.singularities()
mksing = mk.singularities()
mknsing = mkn.singularities()
mssinglist = [
mssing["inner_ergosphere"],
mssing["inner_horizon"],
mssing["outer_horizon"],
mssing["outer_ergosphere"]
]
mksinglist = [
mksing["inner_ergosphere"](theta),
mksing["inner_horizon"],
mksing["outer_horizon"],
mksing["outer_ergosphere"](theta)
]
mknsinglist = [
mknsing["inner_ergosphere"](theta),
mknsing["inner_horizon"],
mknsing["outer_horizon"],
mknsing["outer_ergosphere"](theta)
]
scr = ms.schwarzschild_radius(M)
assert_allclose(mssinglist, mksinglist, rtol=1e-4, atol=0.0)
assert_allclose(mksinglist, mknsinglist, rtol=1e-4, atol=0.0)
assert_allclose(mknsinglist, mssinglist, rtol=1e-4, atol=0.0)
assert_allclose(mksinglist[2], scr, rtol=1e-4, atol=0.0)