#
# Sliding window min/max test (Python)
#
# Copyright (c) 2020 Project Nayuki. (MIT License)
# https://www.nayuki.io/page/sliding-window-minimum-maximum-algorithm
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the "Software"), to deal in
# the Software without restriction, including without limitation the rights to
# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
# the Software, and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
# - The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# - The Software is provided "as is", without warranty of any kind, express or
# implied, including but not limited to the warranties of merchantability,
# fitness for a particular purpose and noninfringement. In no event shall the
# authors or copyright holders be liable for any claim, damages or other
# liability, whether in an action of contract, tort or otherwise, arising from,
# out of or in connection with the Software or the use or other dealings in the
# Software.
#
import random, unittest
import slidingwindowminmax
class SlidingWindowMinMaxTest(unittest.TestCase):
def test_randomly(self):
trials = 3000
for _ in range(trials):
arraylen = random.randrange(300)
array = [random.randrange(100) for _ in range(arraylen)]
window = random.randrange(1, 31)
maximize = random.randrange(2) != 0
expect = _compute_naive(array, window, maximize)
actual = slidingwindowminmax.compute(array, window, maximize)
self.assertEqual(expect, actual)
def test_incremental(self):
trials = 100
for _ in range(trials):
array = [random.randrange(100) for _ in range(1000)]
swm = slidingwindowminmax.SlidingWindowMinMax()
start = 0
end = 0
while start < len(array):
if start == end or (end < len(array) and random.randrange(2) != 0):
swm.add_tail(array[end])
end += 1
else:
swm.remove_head(array[start])
start += 1
assert start <= end
if start < end:
self.assertEqual(min(array[start : end]), swm.get_minimum())
self.assertEqual(max(array[start : end]), swm.get_maximum())
def _compute_naive(array, window, maximize):
if window <= 0:
raise ValueError()
func = max if maximize else min
return [func(array[i : i + window]) for i in range(len(array) - window + 1)]
if __name__ == "__main__":
unittest.main()