def test_zipfian_continuity(self):
# test that zipfian(0.999999, n) ~ zipfian(1.000001, n)
# (a = 1 switches between methods of calculating harmonic sum)
alt1, agt1 = 0.99999999, 1.00000001
N = 30
k = np.arange(1, N + 1)
assert_allclose(zipfian.pmf(k, alt1, N), zipfian.pmf(k, agt1, N))
assert_allclose(zipfian.cdf(k, alt1, N), zipfian.cdf(k, agt1, N))
assert_allclose(zipfian.sf(k, alt1, N), zipfian.sf(k, agt1, N))
assert_allclose(zipfian.stats(alt1, N, moments='msvk'),
zipfian.stats(agt1, N, moments='msvk'), rtol=2e-7)
def test_zipfian_asymptotic(self):
# test limiting case that zipfian(a, n) -> zipf(a) as n-> oo
a = 6.5
N = 10000000
k = np.arange(1, 21)
assert_allclose(zipfian.pmf(k, a, N), zipf.pmf(k, a))
assert_allclose(zipfian.cdf(k, a, N), zipf.cdf(k, a))
assert_allclose(zipfian.sf(k, a, N), zipf.sf(k, a))
assert_allclose(zipfian.stats(a, N, moments='msvk'),
zipf.stats(a, moments='msvk'))