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| 1 | +# # -*- coding:utf-8 -*- |
| 2 | +# &Author AnFany |
| 3 | + |
| 4 | + |
| 5 | + |
| 6 | +# 本文提供8种排序算法 |
| 7 | +import numpy as np |
| 8 | +from prettytable import PrettyTable # 用表格输出时间对比 |
| 9 | +import time |
| 10 | + |
| 11 | + |
| 12 | +paidict = {'Bubble': ['冒泡'], 'Insert': ['直接插入'],'Shell': ['希尔'], |
| 13 | + 'Select': ['直接选择'],'Quick': ['快速'], 'Heap': ['堆'], |
| 14 | + 'Merge': ['归并'], 'sorted': ['Python自带'], 'Radix': ['基数']} |
| 15 | + |
| 16 | +# 直接插入排序 |
| 17 | +def Insert(listdata): |
| 18 | + for i in range(1, len(listdata)): |
| 19 | + # 设置当前值前一个元素的标识 |
| 20 | + j = i - 1 |
| 21 | + # 如果当前值小于前一个元素,则将当前值作为一个临时变量存储,将前一个元素后移一位 |
| 22 | + if listdata[i] < listdata[j]: |
| 23 | + temp, listdata[i] = listdata[i], listdata[j] |
| 24 | + # 继续往前寻找,如果有比临时变量大的数字,则后移一位,直到找到比临时变量小的元素或者达到列表第一个元素 |
| 25 | + j = j - 1 |
| 26 | + while j >= 0 and listdata[j] > temp: |
| 27 | + listdata[j + 1] = listdata[j] |
| 28 | + j = j - 1 |
| 29 | + # 将临时变量赋值给合适位置 |
| 30 | + listdata[j + 1] = temp |
| 31 | + return listdata |
| 32 | + |
| 33 | +# 希尔排序 |
| 34 | +def Shell(listdata): |
| 35 | + n = len(listdata) |
| 36 | + # 希尔增量 |
| 37 | + gap = int(n / 2) |
| 38 | + while gap > 0: |
| 39 | + # 按增量进行直接插入排序 |
| 40 | + for i in range(gap, n): |
| 41 | + j = i |
| 42 | + # 直接插入排序 |
| 43 | + while j >= gap and listdata[j - gap] > listdata[j]: |
| 44 | + listdata[j - gap], listdata[j] = listdata[j], listdata[j - gap] |
| 45 | + j -= gap |
| 46 | + # 得到新的增量 |
| 47 | + gap = int(gap / 2) |
| 48 | + return listdata |
| 49 | + |
| 50 | +# 直接选择排序 |
| 51 | +def Select(listdata): |
| 52 | + for i in range(len(listdata) - 1): |
| 53 | + minnum = i |
| 54 | + for j in range(i + 1, len(listdata)): |
| 55 | + if listdata[j] < listdata[minnum]: |
| 56 | + minnum = j |
| 57 | + listdata[i], listdata[minnum] = listdata[minnum], listdata[i] |
| 58 | + return listdata |
| 59 | + |
| 60 | +# 堆排序 |
| 61 | +def adjust_heap(lists, i, size): |
| 62 | + lchild = 2 * i + 1 |
| 63 | + rchild = 2 * i + 2 |
| 64 | + max = i |
| 65 | + if i < size / 2: |
| 66 | + if lchild < size and lists[lchild] > lists[max]: |
| 67 | + max = lchild |
| 68 | + if rchild < size and lists[rchild] > lists[max]: |
| 69 | + max = rchild |
| 70 | + if max != i: |
| 71 | + lists[max], lists[i] = lists[i], lists[max] |
| 72 | + adjust_heap(lists, max, size) |
| 73 | + |
| 74 | +# 创建堆 |
| 75 | +def build_heap(lists, size): |
| 76 | + for i in range(0, (int(size/2)))[::-1]: |
| 77 | + adjust_heap(lists, i, size) |
| 78 | + |
| 79 | +# 堆排序 |
| 80 | +def Heap(lists): |
| 81 | + size = len(lists) |
| 82 | + build_heap(lists, size) |
| 83 | + for i in range(0, size)[::-1]: |
| 84 | + lists[0], lists[i] = lists[i], lists[0] |
| 85 | + adjust_heap(lists, 0, i) |
| 86 | + return lists |
| 87 | + |
| 88 | +# 基数排序 |
| 89 | +def Radix(listdata): |
| 90 | + k = len(str(max(listdata))) # k获取最大位数 |
| 91 | + for k in range(k): # 遍历位数,从低到高 |
| 92 | + s = [[] for i in range(10)] # 生成存放数的十个桶 |
| 93 | + for i in listdata: # 遍历元素 |
| 94 | + s[i // (10 ** k) % 10].append(i) # 分桶 |
| 95 | + listdata = [a for b in s for a in b] # 合并桶 |
| 96 | + return listdata |
| 97 | + |
| 98 | +# 归并排序 |
| 99 | +def Merge(listdata): |
| 100 | + n = len(listdata) |
| 101 | + |
| 102 | + if n == 1: |
| 103 | + return listdata |
| 104 | + mid = n // 2 |
| 105 | + |
| 106 | + # 对分割的左半部分进行归并排序 |
| 107 | + leftdata = Merge(listdata[:mid]) |
| 108 | + # 对分割的右半部分进行归并排序 |
| 109 | + rightdata = Merge(listdata[mid:]) |
| 110 | + |
| 111 | + # 对排序之后的两部分进行合并 |
| 112 | + # 定义两个游标 |
| 113 | + left, right = 0, 0 |
| 114 | + |
| 115 | + merge_result_li = [] |
| 116 | + left_n = len(leftdata) |
| 117 | + right_n = len(rightdata) |
| 118 | + |
| 119 | + while left < left_n and right < right_n: |
| 120 | + if leftdata[left] <= rightdata[right]: |
| 121 | + merge_result_li.append(leftdata[left]) |
| 122 | + left += 1 |
| 123 | + else: |
| 124 | + merge_result_li.append(rightdata[right]) |
| 125 | + right += 1 |
| 126 | + |
| 127 | + merge_result_li += leftdata[left:] |
| 128 | + merge_result_li += rightdata[right:] |
| 129 | + |
| 130 | + # 将合并后的结果返回 |
| 131 | + return merge_result_li |
| 132 | + |
| 133 | +# 冒泡排序 |
| 134 | +def Bubble(listdata): |
| 135 | + for i in range(len(listdata) - 1): # 这个循环负责设置冒泡排序进行的次数 |
| 136 | + for j in range(len(listdata) - i - 1): # j为列表下标 |
| 137 | + if listdata[j] > listdata[j + 1]: |
| 138 | + listdata[j], listdata[j + 1] = listdata[j + 1], listdata[j] |
| 139 | + return listdata |
| 140 | + |
| 141 | +# 快速排序 |
| 142 | +def Quick(listdata): |
| 143 | + if len(listdata) == 0: |
| 144 | + return [] |
| 145 | + pivots = [x for x in listdata if x == listdata[0]] |
| 146 | + lesser = Quick([x for x in listdata if x < listdata[0]]) |
| 147 | + greater = Quick([x for x in listdata if x > listdata[0]]) |
| 148 | + return lesser + pivots + greater |
| 149 | + |
| 150 | +# 最终的主程序 |
| 151 | +if __name__ == "__main__": |
| 152 | + numpdata = np.arange(1, 100000) |
| 153 | + count = [5, 50, 500, 5000, 50000] |
| 154 | + # 不同数组长度,每种排序算法运行50次的平均值得对比 |
| 155 | + colu = ['排序'] + ['%s条' % f for f in count] |
| 156 | + x = PrettyTable(colu) |
| 157 | + x.title = '不同算法用时(毫秒)对比,随机取数区间[1, 100000]' |
| 158 | + for pa in paidict: |
| 159 | + print(pa) |
| 160 | + timep = [] |
| 161 | + for ci in count: |
| 162 | + np.random.shuffle(numpdata) |
| 163 | + ldata = list(np.random.choice(numpdata, ci)) |
| 164 | + start = time.clock() |
| 165 | + result = eval(pa)(ldata) |
| 166 | + end = time.clock() |
| 167 | + if result == sorted(ldata): |
| 168 | + timep.append('%.5f' % ((end - start) * 1000)) |
| 169 | + else: |
| 170 | + print('排序算法:%s错误' % pa) |
| 171 | + x.add_row([paidict[pa][0]] + timep) |
| 172 | + print(x) |
| 173 | + |
| 174 | + |
| 175 | + |
| 176 | + |
| 177 | + |
| 178 | + |
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