不同 Python 数据类型的搜寻

语言: Python 3.7.2

系统: Win10 Ver. 10.0.17763

主题: 004.01 不同 Python 数据类型的搜寻
最近在做资料搜索比对的案子的时候，发现大量的数据在搜索比对时，速度变的非常慢，慢到完全无法接受，我想要的是 ' 立即 ' 有结果，结果却是要等好几小时，晕！虽然以 Python 来说，肯定比不上 C 或 Assembly 语言，但是还是要想办法提升一下速度。以下是在一万笔数据中，找一万笔数据的各种方法以及所需的时间，虽然最后一个方法 index_list_sort(), 速度快了多，但是我还是觉得不够快，而且这里还只是整数的搜索，如果是字符串呢？如果是副字符串呢？各位如果有更好的方法，也请提示，谢谢！

结果:

0:00:04.734338 : index_sequence0:00:01.139984 : index_list0:00:00.330116 : index_np0:00:00.233343 : index_np_sort0:00:00.223401 : index_dict0:00:00.213462 : index_set0:00:00.007977 : index_list_sort

代码：

代码:from datetime import datetimeimport numpy as npimport bisectimport timeimport randomimport inspectimport copysize = 10000value = size-1db = random.sample(range(size), size)db_sort = copy.deepcopy(db)db_sort.sort()db_set = set(db)db_dict = {db[i]:i for i in range(size)}db_np = np.array(db)value = [i for i in range(size)]def call(func): # Call function and calculate execution time, then print duration and function name start_time = datetime.now() func() print(datetime.now() - start_time,':',func.__name__)def do_something(): # Do something here, it may get duration different when multi-loop method used for i in range(1000): passdef index_sequence(): # List unsort and just by Python without any method used or built-in function. for i in range(size): for j in range(size): if value[j] == db[i]: index = j do_something() breakdef index_list(): # Unsorted list, use list.index() for i in range(size): try: index = db.index(value[i]) except: index = -1 if index >= 0: do_something()def index_np(): # By using numpy and np(where) for i in range(size): result = np.where(db_np==value[i]) if len(result[0])!=0: do_something()def index_np_sort(): # By using numpy and sorted numpy array for i in range(size): result = np.searchsorted(db_np, value[i]) if result != size: do_something()def index_list_sort(): # By using bisect library for i in range(size): index = bisect.bisect_left(db, value[i]) if index < size-1 and value[index]==db[index]: do_something()def index_set(): # Set serach for i in range(size): if value[i] in db_set: do_something()def index_dict(): # Dictionary search for i in range(size): try: index = db_dict[value[i]] except: index = -1 if index >= 0: do_something()Test execution time

call(index_sequence)call(index_list)call(index_np)call(index_np_sort)call(index_dict)call(index_set)call(index_list_sort)复制代码 database search