Add test program for testing q_shuffle function

Add the test program that invoke the q_shuffle command to test
q_shuffle.The program simulates one million shuffle operations,
collects the output, and computes the chi-square sum to assess
the uniformity of the distribution.

Change-Id: I3e619f0267b52b93c934c2682c28cc66c754ea62

Author: charliechiou

test_shuffle.py

@@ -0,0 +1,77 @@
+#!/usr/bin/env python3
+
+import subprocess
+import re
+import random
+from itertools import permutations
+import random
+import matplotlib.pyplot as plt
+import numpy as np
+
+# 測試 shuffle 次數
+test_count = 1000000
+input = "new\nit 1\nit 2\nit 3\nit 4\n"
+for i in range(test_count):
+    input += "shuffle\n"
+input += "free\nquit\n"
+
+# 取得 stdout 的 shuffle 結果
+print("Start testing")
+command = './qtest -v 3'
+clist = command.split()
+completedProcess = subprocess.run(
+    clist, capture_output=True, text=True, input=input)
+s = completedProcess.stdout
+startIdx = s.find("l = [1 2 3 4]")
+endIdx = s.find("l = NULL")
+s = s[startIdx + 14: endIdx]
+Regex = re.compile(r'\d \d \d \d')
+result = Regex.findall(s)
+
+
+def permute(nums):
+    nums = list(permutations(nums, len(nums)))
+    return nums
+
+
+def chiSquared(observation, expectation):
+    return ((observation - expectation) ** 2) / expectation
+
+
+# shuffle 的所有結果
+nums = []
+for i in result:
+    nums.append(i.split())
+
+# 找出全部的排序可能
+counterSet = {}
+shuffle_array = ['1', '2', '3', '4']
+s = permute(shuffle_array)
+
+# 初始化 counterSet
+for i in range(len(s)):
+    w = ''.join(s[i])
+    counterSet[w] = 0
+
+# 計算每一種 shuffle 結果的數量
+for num in nums:
+    permutation = ''.join(num)
+    counterSet[permutation] += 1
+
+# 計算 chiSquare sum
+expectation = test_count // len(s)
+c = counterSet.values()
+chiSquaredSum = 0
+for i in c:
+    chiSquaredSum += chiSquared(i, expectation)
+print("Expectation: ", expectation)
+print("Observation: ", counterSet)
+print("chi square sum: ", chiSquaredSum)
+
+x = np.arange(len(c))
+plt.bar(x, c)
+plt.xticks(x, list(counterSet.keys()))
+plt.xlabel('permutations')
+plt.ylabel('counts')
+plt.title('Shuffle result')
+plt.show()