def test_extract_min(self):
heap, elements = get_random_min_heap()
actual_min = heap_extract_min(heap)
assert_that(actual_min, is_(equal_to(min(elements))))
assert_min_heap(heap)
actual_heap_keys = heap[1:heap.heap_size]
expected_heap_keys = sorted(elements)[1:] # all but minimum
assert_that(actual_heap_keys, contains_inanyorder(*expected_heap_keys))
def test_min_heapify(self):
heap, elements = get_random_min_heap()
i = random.randint(1, heap.heap_size)
heap[i] = elements[i - 1] = random.randint(heap[i], 999) # randomly increase value of randomly chosen element
min_heapify(heap, i)
assert_that(heap.heap_size, is_(equal_to(len(elements))))
assert_min_heap(heap)
assert_that(heap.elements, contains_inanyorder(*elements))
def test_extract_min(self):
heap, elements = get_random_min_heap()
actual_min = heap_extract_min(heap)
assert_that(actual_min, is_(equal_to(min(elements))))
assert_min_heap(heap)
actual_heap_keys = heap[1:heap.heap_size]
expected_heap_keys = sorted(elements)[1:] # all but minimum
assert_that(actual_heap_keys, contains_inanyorder(*expected_heap_keys))
def test_min_heap_insert(self):
heap, elements = get_random_min_heap()
heap.elements.append(None) # to increase the heap's capacity for the new element
heap.length += 1
new_key = random.randrange(1000)
min_heap_insert(heap, new_key)
assert_that(heap.heap_size, is_(equal_to(len(elements) + 1)))
assert_min_heap(heap)
expected_heap_keys = elements + [new_key]
assert_that(heap.elements, contains_inanyorder(*expected_heap_keys))
def test_min_heap_insert(self):
heap, elements = get_random_min_heap()
heap.elements.append(
None) # to increase the heap's capacity for the new element
heap.length += 1
new_key = random.randrange(1000)
min_heap_insert(heap, new_key)
assert_that(heap.heap_size, is_(equal_to(len(elements) + 1)))
assert_min_heap(heap)
expected_heap_keys = elements + [new_key]
assert_that(heap.elements, contains_inanyorder(*expected_heap_keys))
def test_heap_decrease_key(self):
heap, elements = get_random_min_heap()
i = random.randint(1, heap.heap_size)
old_key = heap[i]
new_key = random.randrange(1000)
if new_key > old_key:
assert_that(calling(heap_decrease_key).with_args(heap, i, new_key),
raises(RuntimeError, 'new key is larger than current key'))
else:
heap_decrease_key(heap, i, new_key)
assert_that(heap.heap_size, is_(equal_to(len(elements))))
expected_heap_keys = list(elements)
expected_heap_keys.remove(old_key)
expected_heap_keys.append(new_key)
assert_that(heap.elements, contains_inanyorder(*expected_heap_keys))
def test_priority_dequeue(self):
# create a random min heap of numbers
heap, elements = get_random_min_heap()
# and then transform the numbers to elements with keys and data
expected_elements = []
for i in range(1, heap.heap_size + 1):
heap[i] = Element(heap[i], "element " + str(heap[i]))
expected_elements.append(heap[i])
expected_deleted = min([element for element in heap[1:heap.heap_size]], key=lambda e: e.key)
expected_elements.remove(expected_deleted)
actual_deleted = priority_dequeue(heap)
assert_that(actual_deleted, is_(equal_to(expected_deleted)))
actual_elements = heap[1:heap.heap_size].elements
assert_that(actual_elements, contains_inanyorder(*expected_elements))
def test_heap_decrease_key(self):
heap, elements = get_random_min_heap()
i = random.randint(1, heap.heap_size)
old_key = heap[i]
new_key = random.randrange(1000)
if new_key > old_key:
assert_that(
calling(heap_decrease_key).with_args(heap, i, new_key),
raises(RuntimeError, 'new key is larger than current key'))
else:
heap_decrease_key(heap, i, new_key)
assert_that(heap.heap_size, is_(equal_to(len(elements))))
expected_heap_keys = list(elements)
expected_heap_keys.remove(old_key)
expected_heap_keys.append(new_key)
assert_that(heap.elements,
contains_inanyorder(*expected_heap_keys))
def test_heap_minimum(self):
heap, elements = get_random_min_heap()
actual_min = heap_minimum(heap)
assert_that(actual_min, is_(equal_to(min(elements))))
def test_heap_minimum(self):
heap, elements = get_random_min_heap()
actual_min = heap_minimum(heap)
assert_that(actual_min, is_(equal_to(min(elements))))