async def test_single_sample_with_some_depth(self):
samples = ObliviousDataset.create(Sample([s(1)], s(1)))
self.assertEqual(
reveal(await train(samples, depth=2)),
Branch(0,
threshold=0,
left=Branch(0, threshold=0, left=pruned(), right=pruned()),
right=Branch(0, threshold=0, left=pruned(), right=leaf(1))))
def test_select_best_continuous_attribute(self):
samples = ObliviousDataset.create(Sample([s(1)], s(0)),
Sample([s(2)], s(0)),
Sample([s(3)], s(0)),
Sample([s(4)], s(1)),
Sample([s(5)], s(1)),
continuous=[True])
(best_attribute, threshold) = select_best_attribute(samples)
self.assertEqual(reveal(best_attribute), 0)
self.assertEqual(reveal(threshold), 3)
def test_column_with_public_index(self):
dataset = ObliviousDataset.create(sample(s(0), s(1), s(2)),
sample(s(10), s(11), s(12)),
sample(s(20), s(21), s(22)))
self.assertEqual(reveal(dataset.column(0)), [0, 10, 20])
self.assertEqual(reveal(dataset.column(1)), [1, 11, 21])
self.assertEqual(reveal(dataset.column(2)), [2, 12, 22])
def test_continuous_attributes(self):
dataset = ObliviousDataset.create(Sample([s(0), s(1), s(1)], s(0)),
Sample([s(1), s(2), s(1)], s(1)),
continuous=[False, True, False])
self.assertFalse(dataset.is_continuous(0))
self.assertTrue(dataset.is_continuous(1))
self.assertFalse(dataset.is_continuous(2))
def calculate_gains_for_thresholds(column, outcomes):
gains = column.map(lambda _: None)
is_right = column.map(lambda _: s(0))
selection = [None for _ in range(len(column.values))]
last_considered_value = s(-1)
for index in reversed(range(len(column.values))):
gains.values[index] = calculate_gain(is_right, outcomes)
is_right.values[index] = s(1)
is_duplicate = column.values[index] == last_considered_value
selection[index] = ~is_duplicate
last_considered_value = mpc.if_else(column.is_included(index),
column.values[index],
last_considered_value)
return gains.select(selection)
def test_random_sample(self):
dataset = ObliviousDataset.create(
Sample([s(1), s(2), s(3)], s(4)),
Sample([s(11), s(12), s(13)], s(14)))
randomSamples = [reveal(dataset.choice()) for _ in range(100)]
self.assertIn(Sample([1, 2, 3], 4), randomSamples)
self.assertIn(Sample([11, 12, 13], 14), randomSamples)
async def test_continuous_attribute_with_some_depth(self):
samples = ObliviousDataset.create(Sample([s(1)], s(0)),
Sample([s(2)], s(0)),
Sample([s(3)], s(1)),
Sample([s(4)], s(1)),
Sample([s(5)], s(0)),
continuous=[True])
tree = reveal(await train(samples, depth=2))
self.assertEqual(tree.attribute, 0)
self.assertEqual(tree.threshold, 2)
self.assertTrue(isinstance(tree.left, Branch))
self.assertTrue(isinstance(tree.right, Branch))
self.assertEqual(tree.right.attribute, 0)
self.assertEqual(tree.right.threshold, 4)
def test_sorts_column_and_outcomes_of_array(self):
dataset = ObliviousDataset.create(
Sample([s(2)], s(5)),
Sample([s(1)], s(6)),
Sample([s(3)], s(7)),
Sample([s(4)], s(8))
)
column = dataset.column(s(0))
outcomes = dataset.outcomes
sorted_column, sorted_outcomes = sort(column, outcomes)
self.assertEqual(reveal(sorted_column), [1, 2, 3, 4])
self.assertEqual(reveal(sorted_outcomes), [6, 5, 7, 8])
def maximum(quotients):
"""
Returns both the maximum quotient and the index of the maximum in an
oblivious sequence.
Only works for quotients that have positive numerator and denominator.
"""
def max(previous, current):
(maximum, index_of_maximum, index) = previous
is_new_maximum = ge_quotient(current, maximum)
index_of_maximum = if_else(is_new_maximum, index, index_of_maximum)
maximum = tuple(if_else(is_new_maximum, list(current), list(maximum)))
return (maximum, index_of_maximum, index + 1)
neutral = (s(0), s(0))
initial = (neutral, s(0), s(0))
maximum, index_of_maximum, _ = quotients.reduce(neutral, max, initial)
return maximum, index_of_maximum
def test_gini_gain_mpc(self):
numerator, denominator = gini_gain_quotient(
s(2), s(2), s(1), s(1), s(1), s(1))
numerator = reveal(numerator)
denominator = reveal(denominator)
total = 4
gain = (1 / total) * float(numerator / denominator)
self.assertEqual(gain, 0.5)
def test_reveal_branches(self):
tree = Branch(s(0),
threshold=s(10),
left=Leaf(s(1), pruned=s(False)),
right=Leaf(s(2), pruned=s(True)))
expected_output = Branch(0,
threshold=10,
left=Leaf(1, pruned=False),
right=Leaf(2, pruned=True))
self.assertEqual(reveal(tree), expected_output)
def test_calculate_gains_for_thresholds_ignores_duplicates(self):
samples = ObliviousDataset.create(Sample([s(0)], s(0)),
Sample([s(0)], s(0)),
Sample([s(0)], s(0)),
continuous=[True])
column = samples.column(0)
outcomes = samples.outcomes
gains = calculate_gains_for_thresholds(column, outcomes)
plain_gains = reveal(gains)
self.assertEqual(len(plain_gains), 1)
def calculate_gains(samples):
number_of_attributes = samples.number_of_attributes
gains = []
thresholds = []
outcomes = samples.outcomes
for attribute in range(number_of_attributes):
column = samples.column(attribute)
if samples.is_continuous(attribute):
s_column, s_outcomes = sort(column, outcomes)
(gain, threshold) = select_best_threshold(s_column, s_outcomes)
gains.append(gain)
thresholds.append(threshold)
else:
gain = calculate_gain_for_attribute(column, outcomes)
gains.append(gain)
thresholds.append(s(0))
return gains, thresholds
def test_output_sec_int(self):
self.assertEqual(reveal(s(42)), 42)
def test_column_of_subset_with_secret_index(self):
dataset = ObliviousDataset.create(sample(s(0), s(1), s(2)),
sample(s(10), s(11), s(12)),
sample(s(20), s(21), s(22))).select(
[s(1), s(0), s(1)])
self.assertEqual(reveal(dataset.column(s(1))), [1, 21])
def sample(ins, out):
return Sample([s(i) for i in ins], s(out))
def test_random_sample_with_one_sample(self):
dataset = ObliviousDataset.create(Sample([s(1), s(2), s(3)], s(4)))
self.assertEqual(reveal(dataset.choice()), Sample([1, 2, 3], 4))
def pruned():
return Leaf(s(0), s(True))
def test_classify_with_continuous_attribute(self):
tree = Branch(s(1), s(2), leaf(s(1)), leaf(s(0)))
self.assertEqual(reveal(classify([s(1), s(2), s(1)], tree)), 1)
self.assertEqual(reveal(classify([s(1), s(3), s(1)], tree)), 0)
def test_determine_class_multiple_samples(self):
dataset = ObliviousDataset.create(Sample([s(0)], s(0)),
Sample([s(0)], s(1)),
Sample([s(0)], s(1)))
self.assertEqual(reveal(dataset.determine_class()), 1)
def sample(*inputs):
return Sample(inputs, s(0))
def test_outcomes(self):
dataset = ObliviousDataset.create(
Sample([s(0), s(1), s(2)], outcome=s(60)),
Sample([s(10), s(11), s(12)], outcome=s(70)),
Sample([s(20), s(21), s(22)],
outcome=s(80))).select([s(1), s(0), s(1)])
self.assertEqual(reveal(dataset.outcomes), [60, 80])
def test_classify_with_a_branch(self):
tree = Branch(s(1), s(0), leaf(s(1)), leaf(s(0)))
self.assertEqual(reveal(classify([s(1), s(0), s(1)], tree)), 1)
self.assertEqual(reveal(classify([s(1), s(1), s(1)], tree)), 0)
def test_tuple(self):
chosen = if_else(s(True), (s(1), s(2)), (s(3), s(4)))
self.assertEqual(reveal(chosen), (1, 2))
def test_classify_with_pruned_subtree(self):
tree = Branch(s(1), s(0), Branch(s(0), s(0), pruned(), pruned()),
Branch(s(2), s(0), leaf(s(0)), leaf(s(1))))
self.assertEqual(reveal(classify([s(0), s(0), s(1)], tree)), 1)
def test_number_of_attributes(self):
dataset = ObliviousDataset.create(sample(s(1), s(2), s(3)),
sample(s(4), s(5), s(6)))
self.assertEqual(dataset.number_of_attributes, 3)
def leaf(outcome):
return Leaf(outcome, s(False))
def test_add_samples(self):
sample1 = Sample([s(1), s(2), s(3)], s(4))
sample2 = Sample([s(5), s(6), s(7)], s(8))
self.assertEqual(reveal(sample1 + sample2), Sample([6, 8, 10], 12))
def test_classify_with_only_leaf_node(self):
sample = [s(1), s(0), s(1)]
tree = leaf(s(1))
self.assertEqual(reveal(classify(sample, tree)), 1)
def test_continuous_attribute_check_with_secret_index(self):
dataset = ObliviousDataset.create(Sample([s(0), s(1), s(1)], s(0)),
Sample([s(1), s(2), s(1)], s(1)),
continuous=[False, True, False])
self.assertFalse(reveal(dataset.is_continuous(s(0))))
self.assertTrue(reveal(dataset.is_continuous(s(1))))
self.assertFalse(reveal(dataset.is_continuous(s(2))))
