def testAllSequences(self):
event = probability.FiniteProductEvent([
probability.DiscreteEvent({1, 2}),
probability.DiscreteEvent({3})
])
all_sequences = [i for i in event.all_sequences()]
self.assertEqual(all_sequences, [(1, 3), (2, 3)])
def testProbability_FiniteProductEvent(self):
# 5 coin flips of a biased coin with heads prob = 1/3.
base_space = probability.DiscreteProbabilitySpace({'h': 1, 't': 2})
space = probability.FiniteProductSpace([base_space] * 5)
heads = probability.DiscreteEvent({'h'})
tails = probability.DiscreteEvent({'t'})
event = probability.FiniteProductEvent(
[heads, heads, tails, tails, heads])
self.assertEqual(space.probability(event), sympy.Rational(4, 3**5))
def testInverse_FiniteProductEvent(self):
rv = self._random_variable()
event1 = probability.DiscreteEvent({'a', 'b'})
event2 = probability.DiscreteEvent({'x'})
event = probability.FiniteProductEvent((event1, event2))
result = rv.inverse(event)
self.assertIsInstance(result, probability.FiniteProductEvent)
self.assertLen(result.events, 2)
self.assertEqual(result.events[0].values, {1, 2})
self.assertEqual(result.events[1].values, {1, 3})
def testBasic(self):
space = probability.DiscreteProbabilitySpace({0: 1, 1: 2, 2: 3})
p = space.probability(probability.DiscreteEvent([0]))
self.assertEqual(p, sympy.Rational(1, 6))
p = space.probability(probability.DiscreteEvent([0, 1]))
self.assertEqual(p, sympy.Rational(1, 2))
p = space.probability(probability.DiscreteEvent([0, 1, 2]))
self.assertEqual(p, 1)
p = space.probability(probability.DiscreteEvent([0, 1, 2, 3]))
self.assertEqual(p, 1)
p = space.probability(probability.DiscreteEvent([3]))
self.assertEqual(p, 0)
def testInverse(self):
random_variable = probability.DiscreteRandomVariable({
1: 1,
2: 3,
3: 4
})
inverse = random_variable.inverse(probability.DiscreteEvent({1, 3}))
self.assertEqual(inverse.values, {1, 2})
random_variable = probability.DiscreteRandomVariable({1: 1, 2: 1})
inverse = random_variable.inverse(probability.DiscreteEvent({1, 5}))
self.assertEqual(inverse.values, {1, 2})
def testCall(self):
random_variable = probability.DiscreteRandomVariable({
1: 1,
2: 3,
3: 4
})
forwards = random_variable(probability.DiscreteEvent({1, 3}))
self.assertEqual(forwards.values, {1, 4})
def testBasic(self):
space = probability.SampleWithoutReplacementSpace({0: 1, 1: 1}, 2)
event_0_0 = probability.FiniteProductEvent(
[probability.DiscreteEvent({0}),
probability.DiscreteEvent({0})])
event_0_1 = probability.FiniteProductEvent(
[probability.DiscreteEvent({0}),
probability.DiscreteEvent({1})])
p_0_0 = space.probability(event_0_0)
p_0_1 = space.probability(event_0_1)
self.assertEqual(p_0_0, 0)
self.assertEqual(p_0_1, sympy.Rational(1, 2))
space = probability.SampleWithoutReplacementSpace({0: 1, 1: 0}, 1)
event_0 = probability.FiniteProductEvent(
[probability.DiscreteEvent({0})])
event_1 = probability.FiniteProductEvent(
[probability.DiscreteEvent({1})])
event_2 = probability.FiniteProductEvent(
[probability.DiscreteEvent({2})])
p_0 = space.probability(event_0)
p_1 = space.probability(event_1)
p_2 = space.probability(event_2)
self.assertEqual(p_0, 1)
self.assertEqual(p_1, 0)
self.assertEqual(p_2, 0)
def _sequence_event(values, length, verb):
"""Returns sequence (finite product) event.
Args:
values: List of values to sample from.
length: Length of the sequence to generate.
verb: Verb in infinitive form.
Returns:
Instance of `probability.FiniteProductEvent`, together with a text
description.
"""
del verb # unused
samples = [random.choice(values) for _ in range(length)]
events = [probability.DiscreteEvent([sample]) for sample in samples]
event = probability.FiniteProductEvent(events)
sequence = ''.join(str(sample) for sample in samples)
event_description = 'последовательности {sequence}'.format(
sequence=sequence)
return event, event_description