python 如何让时间识别定义的输入

Question

我有一个 df 定义，我正在成功地运行操作。我想计算迭代for循环和矢量化操作之间的差异。我已经阅读了有关如何使用 timeit 的各种示例，但是当我尝试使用它们时，出现以下错误。我究竟做错了什么？进口：import h5pyimport pandas as pdimport timeit这个循环有效：for u in df['owner'].unique():    print(u, ': ', len(df[(df['owner'] == u)]), sep = '')但是当我尝试这样计时时......：s = """\for u in df['owner'].unique():    print(u, ': ', len(df[(df['owner'] == u)]), sep = '')"""time_iter_1_1_1 = timeit.timeit(s)...它产生这个错误：---------------------------------------------------------------------------NameError                                 Traceback (most recent call last)<ipython-input-34-7526e96d565c> in <module>()      3 #     print(u, ': ', len(df[(df['owner'] == u)]), sep = '')""")      4 ----> 5 time_iter_1_1_1 = timeit.timeit(s)~\Anaconda2\envs\py36\lib\timeit.py in timeit(stmt, setup, timer, number, globals)    231            number=default_number, globals=None):    232     """Convenience function to create Timer object and call timeit method."""--> 233     return Timer(stmt, setup, timer, globals).timeit(number)    234     235 def repeat(stmt="pass", setup="pass", timer=default_timer,~\Anaconda2\envs\py36\lib\timeit.py in timeit(self, number)    176         gc.disable()    177         try:--> 178             timing = self.inner(it, self.timer)    179         finally:    180             if gcold:~\Anaconda2\envs\py36\lib\timeit.py in inner(_it, _timer)NameError: name 'df' is not defined当我尝试这个时......：time_iter_1_1_1 = timeit.timeit("""for u in df['owner'].unique():    print(u, ': ', len(df[(df['owner'] == u)]), sep = '')""")...我收到此错误：ERROR:root:An unexpected error occurred while tokenizing inputThe following traceback may be corrupted or invalidThe error message is: ('EOF in multi-line string', (1, 57))...NameError: name 'df' is not defineddf 已定义并正常工作。我怎样才能解决这个问题？

Answer 1

有两种选择，要么

传递一个globals允许timeit解析名称的参数，

df = pd.DataFrame(...)

timeit.timeit(statement, globals={'df': df}) # globals=globals()

...或者，传递一个为您setup设置的字符串参数df。

timeit.timeit(statement, setup='import pandas as pd; df = pd.DataFrame(...)')