def test_2(self):
pq = MinPQ([5, 4, 3, 2, 1])
self.assertEqual(pq.size(), 5)
self.assertTrue(pq.capacity == 5)
self.assertTrue(pq.capacity == pq.num_items)
self.assertTrue(pq.arr == [1, 2, 3, 5, 4])
self.assertEqual(pq.min(), 1)
self.assertEqual(pq.del_min(), 1)
self.assertEqual(pq.del_min(), 2)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 4)
self.assertEqual(pq.del_min(), 5)
self.assertTrue(pq.capacity == 2)
self.assertEqual(pq.size(), 0)
self.assertTrue(pq.is_empty())
def test_use_case_one(self):
""" Implementation of use case 1 as outlined in lab instructions"""
pq_test = MinPQ()
pq_test.insert(5)
pq_test.insert(3)
self.assertTrue(pq_test.capacity == 2)
pq_test.insert(6)
self.assertEqual(3, pq_test.size())
self.assertEqual(3, pq_test.min())
self.assertEqual(3, pq_test.del_min())
self.assertEqual(5, pq_test.del_min())
self.assertEqual(6, pq_test.del_min())
self.assertEqual(0, pq_test.size())
self.assertTrue(pq_test.is_empty())
self.assertEqual(2, pq_test.capacity)
def test_1(self):
pq = MinPQ()
pq.insert(5)
pq.insert(3)
self.assertEqual(pq.capacity, 2)
pq.insert(6)
self.assertEqual(pq.size(), 3)
self.assertTrue(pq.capacity == 4)
self.assertEqual(pq.min(), 3)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 5)
self.assertEqual(pq.del_min(), 6)
self.assertEqual(pq.size(), 0)
self.assertTrue(pq.is_empty())
self.assertTrue(pq.capacity == 2)
def test_pq2(self):
pq = MinPQ()
self.assertTrue(pq.is_empty())
for i in reversed(range(5)):
print("pq.insert(", i, ")")
pq.insert(i)
self.assertEqual(pq.size(), 5)
self.assertFalse(pq.is_empty())
self.assertEqual(pq.min(), 0)
self.assertEqual(pq.del_min(), 0)
self.assertEqual(pq.del_min(), 1)
self.assertEqual(pq.del_min(), 2)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 4)
self.assertTrue(pq.is_empty())
self.assertEqual(pq.size(), 0)
def test_full_functionality(self):
""" Tests the bulk functionality of the MinPQ class"""
pq_test = MinPQ()
pq_test.insert(6)
self.assertEqual(2, pq_test.capacity)
self.assertEqual(pq_test.size(), pq_test.num_items)
pq_test.insert(7)
self.assertEqual([6, 7], pq_test.arr)
pq_test.insert(2)
self.assertEqual(3, pq_test.size())
self.assertEqual([2, 7, 6, None], pq_test.arr)
self.assertFalse(pq_test.is_empty())
self.assertEqual(2, pq_test.del_min())
self.assertEqual(6, pq_test.del_min())
self.assertEqual(7, pq_test.del_min())
self.assertTrue(pq_test.is_empty())
def test_use_case_two(self):
""" Implementation of use case 2 as outlined in lab instructions"""
pq_test = MinPQ([5, 4, 3, 2, 1])
self.assertEqual(5, pq_test.size())
self.assertEqual(5, pq_test.capacity)
self.assertEqual(pq_test.num_items, pq_test.capacity)
self.assertTrue(pq_test.arr == [1, 2, 3, 5, 4])
self.assertEqual(1, pq_test.min())
self.assertEqual(1, pq_test.del_min())
self.assertEqual(2, pq_test.del_min())
self.assertFalse(pq_test.is_empty())
self.assertEqual(3, pq_test.del_min())
self.assertEqual(4, pq_test.del_min())
self.assertEqual(5, pq_test.del_min())
self.assertEqual(2, pq_test.capacity)
self.assertEqual(0, pq_test.size())
self.assertTrue(pq_test.is_empty())
def test_pq(self):
pq = MinPQ([3, 10, 231, 5])
self.assertEqual(pq.is_empty(), False)
self.assertEqual(pq.size(), 4)
self.assertEqual(pq.capacity, 4)
self.assertEqual(pq.min(), 3)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 5)
self.assertEqual(pq.del_min(), 10)
self.assertEqual(pq.del_min(), 231)
self.assertRaises(IndexError, pq.min)
self.assertRaises(IndexError, pq.del_min)
self.assertEqual(pq.is_empty(), True)
self.assertEqual(pq.num_items, 0)
def create_huff_tree(list_of_freqs):
""" Create a Huffman Tree from list of character frequencies
Args:
list_of_freqs(list): list with length of 256 characters
Returns:
MinPQ: the root node of the Min Priority Queue constructed from
the Huffman Nodes
"""
priority_queue_list = []
for each in range(len(list_of_freqs)):
if list_of_freqs[each] > 0:
char = chr(each)
freq = list_of_freqs[each]
node = HuffmanNode(freq, char)
priority_queue_list.append(node)
priority_queue = MinPQ(priority_queue_list)
if priority_queue.size() == 0:
return None
while priority_queue.size() > 1:
# Retrieves the two smallest occurring Nodes from the queue
node_1 = priority_queue.del_min()
node_2 = priority_queue.del_min()
# Determine the representation of the min chr representation
min_chr = min(node_1.char, node_2.char)
# Sum the different frequencies, create new Node, and add to queue
sum_freq = node_1.freq + node_2.freq
new_node = HuffmanNode(sum_freq, min_chr, node_1, node_2)
priority_queue.insert(new_node)
return priority_queue.del_min()
def test_pq4(self):
arr = [5, 2, 3, 4, 1]
print(arr)
pq = MinPQ(arr)
print("pq.heapify(",arr,")")
self.assertEqual(pq.size(), 5)
self.assertEqual(pq.capacity, 5)
self.assertFalse(pq.is_empty())
self.assertEqual(pq.min(), 1)
self.assertEqual(pq.del_min(), 1)
self.assertEqual(pq.del_min(), 2)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 4)
self.assertEqual(pq.del_min(), 5)
self.assertTrue(pq.is_empty())
def create_huff_tree(list_of_freqs):
"""Creates a huffman tree given a list of character frequencies.
Arguments:
list_of_freqs (list): List of character frequencies from cnt_freq()
Returns:
The root node of the huffman tree created from the list of frequencies
"""
pq_arr = []
for char, freq in enumerate(list_of_freqs):
if freq > 0:
pq_arr.append(HuffmanNode(chr(char), freq, None, None))
min_pq = MinPQ(pq_arr)
while min_pq.size() > 1:
left = min_pq.del_min()
right = min_pq.del_min()
min_char = min(left.char, right.char)
parent_node = HuffmanNode(min_char, left.freq + right.freq, left, right)
min_pq.insert(parent_node)
return min_pq.min()
def test_min_pq(self):
minq = MinPQ([5, 4, 3, 2, 1, 0])
minq2 = MinPQ()
minq2.insert(0)
minq2.insert(1)
self.assertEqual(minq2.capacity, 2)
minq2.insert(2)
self.assertEqual(minq2.capacity, 4)
minq2.insert(3)
minq2.insert(4)
minq2.insert(5)
self.assertEqual(minq2.min(), 0)
minq2.del_min()
self.assertEqual(minq2.min(), 1)
self.assertEqual(minq2.size(), 5)
minq2.del_min()
minq2.del_min()
self.assertEqual(minq2.capacity, 8)
minq2.del_min()
self.assertEqual(minq2.capacity, 4)
minq2.del_min()
minq2.del_min()
self.assertRaises(IndexError, minq2.del_min)
class MinPQTests(unittest.TestCase):
def setUp(self):
self.pq1 = MinPQ()
self.pq2 = MinPQ()
def test_eq_repr(self):
self.assertEqual(repr(self.pq1), 'MinPQ([None, None])')
self.assertEqual(self.pq1, self.pq2)
self.assertEqual(self.pq1.size(), 0)
self.assertEqual(self.pq2.size(), 0)
self.pq1.insert(0)
self.pq1.insert(4)
self.pq1.insert(3)
self.pq2.insert(4)
self.pq2.insert(3)
self.pq2.insert(0)
self.assertEqual(repr(self.pq1), 'MinPQ([0, 4, 3, None])')
self.assertEqual(self.pq1.size(), 3)
self.assertEqual(self.pq1.min(), 0)
self.assertEqual(self.pq1, self.pq2)
def test_heapify(self):
pq = MinPQ([9, 6, 5, 2, 3])
self.assertEqual(pq.arr, [2, 3, 5, 6, 9])
pq = MinPQ([6, 3, 7, 2, 8, 1])
self.assertEqual(pq.arr, [1, 2, 6, 3, 8, 7])
pq = MinPQ([1, 3, 6, 8])
self.assertEqual(pq.arr, [1, 3, 6, 8])
def test_insert_del_size(self):
self.assertRaises(IndexError, self.pq1.del_min)
self.pq1.insert(1)
self.assertEqual(self.pq1.size(), 1)
self.assertEqual(self.pq1.arr, [1, None])
self.pq1.insert(6)
self.assertEqual(self.pq1.size(), 2)
self.assertEqual(self.pq1.arr, [1, 6])
self.pq1.insert(5)
self.assertEqual(self.pq1.size(), 3)
self.assertEqual(self.pq1.arr, [1, 6, 5, None])
self.assertEqual(self.pq1.del_min(), 1)
self.assertEqual(self.pq1.arr, [5, 6, None, None])
self.pq1.insert(1)
self.assertEqual(self.pq1.arr, [1, 6, 5, None])
def test_1(self):
pq = MinPQ()
pq.insert(5)
pq.insert(3)
self.assertEqual(pq.capacity, 2)
pq.insert(6)
self.assertEqual(pq.size(), 3)
self.assertTrue(pq.capacity == 4)
self.assertEqual(pq.min(), 3)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 5)
self.assertEqual(pq.del_min(), 6)
self.assertEqual(pq.size(), 0)
self.assertTrue(pq.is_empty())
self.assertTrue(pq.capacity == 2)
def test_2(self):
pq = MinPQ([5, 4, 3, 2, 1])
self.assertEqual(pq.size(), 5)
self.assertTrue(pq.capacity == 5)
self.assertTrue(pq.capacity == pq.num_items)
self.assertTrue(pq.arr == [1, 2, 3, 5, 4])
self.assertEqual(pq.min(), 1)
self.assertEqual(pq.del_min(), 1)
self.assertEqual(pq.del_min(), 2)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 4)
self.assertEqual(pq.del_min(), 5)
self.assertTrue(pq.capacity == 2)
self.assertEqual(pq.size(), 0)
self.assertTrue(pq.is_empty())
