1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
|
#!/usr/bin/env python
import unittest
import sys
def forward_difference(order, nums):
# Check if valid order is passed
if order < 1:
raise ValueError("Order should be a positive integer")
diff = nums
# Calculate the nth order forward difference series
for i in range(order):
temp = []
for j in range(len(diff) - 1):
try:
temp.append(diff[j + 1] - diff[j])
except TypeError:
raise TypeError(f"not a number")
diff = temp
# Return the final series
return diff
# Main code
if __name__ == '__main__':
# Parse command line arguments
nums = []
for arg in sys.argv[1:-1]:
try:
nums.append(int(arg))
except ValueError:
raise ValueError(f"Invalid argument: {arg!r}")
order = int(sys.argv[-1])
# Calculate the nth order forward difference series
diff = forward_difference(order, nums)
# Print the final series
print(', '.join(map(str, diff)))
# Tests
class TestForwardDifference(unittest.TestCase):
def test_first_order(self):
nums = [5, 9, 2, 8, 1, 6]
expected_diff = [4, -7, 6, -7, 5]
actual_diff = forward_difference(1, nums)
self.assertListEqual(expected_diff, actual_diff)
def test_second_order(self):
nums = [5, 9, 2, 8, 1, 6]
expected_diff = [-11, 13, -13, 12]
actual_diff = forward_difference(2, nums)
self.assertListEqual(expected_diff, actual_diff)
def test_invalid_order(self):
nums = [5, 9, 2, 8, 1, 6]
with self.assertRaises(ValueError):
forward_difference(-1, nums)
def test_non_numeric_parameters(self):
nums = [5, 9, 2, 8, "foo", 6]
with self.assertRaises(TypeError):
forward_difference(2, nums)
if __name__ == '__main__':
unittest.main()
|
