def test_sample_rows():
"""Sampling ratings when dataframe has non-unique indices"""
ratings = lktu.ml_test.ratings
ratings = ratings.set_index('user') ##forces non-unique index
with pytest.raises(ValueError):
for split in xf.sample_rows(ratings, partitions=5, size=1000):
pass
def test_sample_oversize():
ratings = lktu.ml_test.ratings
splits = xf.sample_rows(ratings, 50, 10000)
splits = list(splits)
assert len(splits) == 50
for s in splits:
assert len(s.test) + len(s.train) == len(ratings)
assert all(s.test.index.union(s.train.index) == ratings.index)
test_idx = s.test.set_index(['user', 'item']).index
train_idx = s.train.set_index(['user', 'item']).index
assert len(test_idx.intersection(train_idx)) == 0
def test_sample_non_disjoint():
ratings = lktu.ml_test.ratings
splits = xf.sample_rows(ratings, partitions=10, size=1000, disjoint=False)
splits = list(splits)
assert len(splits) == 10
for s in splits:
assert len(s.test) == 1000
assert len(s.test) + len(s.train) == len(ratings)
test_idx = s.test.set_index(['user', 'item']).index
train_idx = s.train.set_index(['user', 'item']).index
assert len(test_idx.intersection(train_idx)) == 0
# There are enough splits & items we should pick at least one duplicate
ipairs = ((s1.test.set_index('user', 'item').index,
s2.test.set_index('user', 'item').index)
for (s1, s2) in it.product(splits, splits))
isizes = [len(i1.intersection(i2)) for (i1, i2) in ipairs]
assert any(n > 0 for n in isizes)
def test_sample_rows_more_smaller_parts():
ratings = lktu.ml_test.ratings
splits = xf.sample_rows(ratings, partitions=10, size=500)
splits = list(splits)
assert len(splits) == 10
for s in splits:
assert len(s.test) == 500
assert len(s.test) + len(s.train) == len(ratings)
test_idx = s.test.set_index(['user', 'item']).index
train_idx = s.train.set_index(['user', 'item']).index
assert len(test_idx.intersection(train_idx)) == 0
for s1, s2 in it.product(splits, splits):
if s1 is s2:
continue
i1 = s1.test.set_index(['user', 'item']).index
i2 = s2.test.set_index(['user', 'item']).index
inter = i1.intersection(i2)
assert len(inter) == 0
