def test_multiple_weathering_steps():
print '\nTesting if we can perform multiple sequential weathering steps'
wc = weather_curve(((.5, 12),
(.5, 24)))
print 'step 1'
res = wc.weather(100, 24, update_fractions=True)
assert np.allclose(res, (12.5 + 25.,))
print 'step 2'
expected = np.asarray(((res.sum() / 3) / 4,
(res.sum() * 2 / 3) / 2,
),
dtype=np.float64)
res = wc.weather(res, 24, update_fractions=True)
assert np.allclose(res, expected.sum())
print '\nTesting if we can perform multiple sequential weathering steps ',
print 'using the explicit method'
wc = weather_curve(((.5, 12),
(.5, 24)))
print 'step 1'
res = wc.weather(100, 24)
assert np.allclose(res, (12.5 + 25.,))
print 'step 2'
expected = np.asarray(((res.sum() / 3) / 4,
(res.sum() * 2 / 3) / 2,
),
dtype=np.float64)
wc.update_fractions(24)
res = wc.weather(res, 24)
assert np.allclose(res, expected.sum())
def test_weather_long_time():
wc = weather_curve(((0.3, 12),
(0.3, 24),
(0.4, 1e10)),
)
time = 1e10
assert np.allclose(wc.weather(100, time), 0.4 * 50.0)
def test_weather_all_add_up():
with raises(ValueError):
wc = weather_curve(((0.5, 12),
(0.5, 24),
(0.5, 36)),
)
print wc
def test_multiple_decay_times():
wc = weather_curve(((0.333333, 12),
(0.333333, 12),
(0.333334, 12)))
print '\nTesting if we can pass multiple decay times',
print ' into our weather() function.'
with raises(ValueError):
res = wc.weather(100, (12, 24, 36))
def test_weather_five_component2():
wc = weather_curve(((.2, 50),
(.2, 50),
(.2, 50),
(.2, 50),
(.2, 50)),
)
time = 50
print wc.weather(100, time)
assert np.allclose(wc.weather(100, time), 50.0)
def test_multiple_initial_masses():
wc = weather_curve(((0.333333, 12),
(0.333333, 12),
(0.333334, 12)))
print '\nTesting if we can pass multiple initial masses',
print 'into our weather() function'
res = wc.weather((100, 200, 300), 12)
print res
assert np.allclose(res, (50., 100., 150.))
res = wc.weather((100, 200, 300), 24)
print res
assert np.allclose(res, (25., 50., 75.))
def test_weather_array():
# this also tests all components the same
wc = weather_curve(((0.3, 24),
(0.3, 24),
(0.4, 24)),
)
time = np.array([24, 48, 72])
mass = np.array([100, 1000, 10000])
# This is old behavior which now raises an exception
#result = np.array([50, 250, 1250], np.float32)
with raises(ValueError):
wc.weather(mass, time)
def test_weather_ten_component():
wc = weather_curve(((.1, 25),
(.1, 25),
(.1, 25),
(.1, 25),
(.1, 25),
(.1, 50),
(.1, 50),
(.1, 50),
(.1, 50),
(.1, 50)),
)
time = 50
assert np.allclose(wc.weather(100, time), 37.5)
def test_mean_lifetime_method():
# Test out our mean lifetime method
# Basically our function is M_0 * exp(-time/tau)
# half-life = tau * ln(2)
# tau = half-life / ln(2)
# So if our half life is 12 hrs,
# tau = (12 / np.log(2)) = 17.312340490667562
print '\nTesting our mean lifetime method'
wc = weather_curve(((0.333333, (12 / np.log(2))),
(0.333333, (12 / np.log(2))),
(0.333334, (12 / np.log(2)))),
method='mean-lifetime'
)
res = wc.weather((100, 200, 300), 12)
print res
assert np.allclose(res, (50., 100., 150.))
def test_decay_constant_method():
# Test out our decay constant method
# Basically our function is M_0 * exp(-time * lambda)
# half-life = ln(2) / lambda
# lambda * half-life = ln(2)
# lambda = ln(2) / half-life
# So if our half life is 12 hrs,
# lambda = (np.log(2) / 12) = 0.057762265046662105
print '\nTesting our decay constant method'
wc = weather_curve(((0.333333, (np.log(2) / 12)),
(0.333333, (np.log(2) / 12)),
(0.333334, (np.log(2) / 12))),
method='decay-constant'
)
res = wc.weather((100, 200, 300), 12)
print res
assert np.allclose(res, (50., 100., 150.))
def test_weather_four_component():
'''
this one with different half-lives for each component
'''
wc = weather_curve(((.2, 120),
(.2, 60),
(.2, 40),
(.2, 30),
(.2, 24)),
)
# num_half-lives: 1 2 3 4 5
# 120 is divisible by 2, 3, 4, 5, 6
M_0 = 100
time = 120
expected = (M_0 * .2) * (1.0 / 2 + 1.0 / 4 + 1.0 / 8 + 1.0 / 16 + 1.0 / 32)
print (M_0 * .25 / 2,
M_0 * .25 / 4,
M_0 * .25 / 8,
M_0 * .25 / 16)
assert np.allclose(wc.weather(M_0, time), expected)
def test_individual_timesteps_one():
'''
tests to see if we get the same results calling weather many times
for a number of time steps, rather than all at once
NOTE: this is only expected to work with one component!
More than one, and the fractions will change as the components
decay at different rates.
'''
# for a single component
wc = weather_curve(((1.0, 24),))
dt = 1.0
num_steps = 10
m_0 = 100.0
m = m_0
for i in range(num_steps):
print i,
m = (wc.weather(m, dt))
print
assert np.allclose(m, wc.weather(m_0, dt * num_steps))
def test_weather_single_component_10():
wc = weather_curve(((1.0, 36),))
time = 36 * 10
assert wc.weather(128, time) == 128. / (2. ** 10)
def test_weather_single_component_4():
wc = weather_curve(((1.0, 36),))
time = 36 * 4
assert wc.weather(128, time) == 8
def test_weather_single_component2():
wc = weather_curve(((1.0, 24),))
time = 48
assert wc.weather(100, time) == 25.0
def test_weather_single_component1():
wc = weather_curve(((1.0, 12),))
time = 12
assert wc.weather(100, time) == 50.0
def test_weather_all_add_up2():
wc = weather_curve(((0.333333, 12),
(0.333333, 24),
(0.333334, 36)),
)
print wc
