def test_correct_num_active_items():
sketch = make_sketch_and_track(ALL_VALS)
assert sketch.get_num_active_items() == 13
sketch = dsketch.FrequentItemsSketch()
assert sketch.get_num_active_items() == 0
sketch.update(1)
assert sketch.get_num_active_items() == 1
def test_null_lg_max_k_protobuf_value():
sketch = dsketch.FrequentItemsSketch()
sketch.lg_max_k = None
msg = sketch.to_protobuf()
assert msg.lg_max_k == -1
sketch2 = dsketch.FrequentItemsSketch.from_protobuf(msg)
assert sketch2.lg_max_k is None
def test_apriori_error_equal_datasketches_error():
# Try it out for a few combos of map sizes
map_sizes = [1, 2, 32, 120]
weights = [0, 10, 50, 100]
sketch = dsketch.FrequentItemsSketch(LG_K)
strings_sketch = datasketches.frequent_strings_sketch(LG_K)
for map_size, w in zip(map_sizes, weights):
assert sketch.get_apriori_error(map_size, w) == strings_sketch.get_apriori_error(map_size, w)
def test_copy_returns_correct_type():
# Empty sketch
sketch = dsketch.FrequentItemsSketch()
copy = sketch.copy()
assert type(copy) == type(sketch)
# Sketch with an item
sketch.update(1)
copy = sketch.copy()
assert type(copy) == type(sketch)
def test_merge_empty_gives_same_result():
# Make sketches
sketch = make_sketch_and_track(ALL_VALS)
empty = dsketch.FrequentItemsSketch()
items = sketch.get_frequent_items()
# Merge empty into full
merged = sketch.merge(empty)
compare_frequent_items(items, merged.get_frequent_items())
# Merge full into empty
merged = empty.merge(sketch)
compare_frequent_items(items, merged.get_frequent_items())
def test_total_weight_correct():
# Default weights
sketch = make_sketch_and_track(STRINGS)
assert sketch.get_total_weight() == len(STRINGS)
# Integer weights
sketch = dsketch.FrequentItemsSketch()
weights = list(range(len(ALL_VALS)))
for v, w in zip(ALL_VALS, weights):
sketch.update(v, w)
assert sketch.get_total_weight() == sum(weights)
def test_empty_sketch_summary_returns_none():
sketch = dsketch.FrequentItemsSketch()
summary = sketch.to_summary()
assert summary is None
def test_copy_empty_returns_empty():
sketch = dsketch.FrequentItemsSketch()
assert sketch.copy().is_empty()
def test_empty_sketch_returns_empty():
assert dsketch.FrequentItemsSketch(32).is_empty()
def make_sketch_and_track(vals=[], lg_k=LG_K):
sketch = dsketch.FrequentItemsSketch(lg_k)
for v in vals:
sketch.update(v)
return sketch
def test_string_epsilon_equals_datasketches():
sketch = dsketch.FrequentItemsSketch(LG_K)
strings_sketch = datasketches.frequent_strings_sketch(LG_K)
for lg in [1, 3, 32, 120]:
assert sketch.get_epsilon_for_lg_size(lg) == strings_sketch.get_epsilon_for_lg_size(lg)
