python - 如何使用 line_profiler(来自 Robert Kern)？

Question

我尝试使用 line_profiler 模块来获取 Python 文件的逐行配置文件。这是我到目前为止所做的:

1) 从 pypi 安装 line_profiler通过使用 .exe 文件(我在 WinXP 和 Win7 上)。只需点击安装向导即可。

2) 编写一小段代码(类似于在另一个已回答的问题 here 中提出的问题)。

from line_profiler import LineProfiler
def do_stuff(numbers):
    print numbers

numbers = 2
profile = LineProfiler(do_stuff(numbers))
profile.print_stats()

3) 从 IDLE/PyScripter 运行代码。我只有时间。

Timer unit: 4.17188e-10 s

如何获得我执行的代码的完整的逐行配置文件？我从未使用过任何高级 Python 功能，如装饰器，所以我很难理解如何使用几篇文章提供的指南，如 here和 here .

Answer 1

此答案是我的答案 here 的副本了解如何从 Python 脚本中获取 line_profiler 统计信息(无需从命令行使用 kernprof 或必须将 @profile 装饰器添加到函数和类方法)。类似 line_profiler 问题的所有答案(我见过)仅使用 kernprof 进行描述。

---

line_profiler 测试用例(在 GitHub 上找到)有一个示例，说明如何从 Python 脚本中生成配置文件数据。您必须包装要分析的函数，然后调用包装器传递任何所需的函数参数。

from line_profiler import LineProfiler
import random

def do_stuff(numbers):
    s = sum(numbers)
    l = [numbers[i]/43 for i in range(len(numbers))]
    m = ['hello'+str(numbers[i]) for i in range(len(numbers))]

numbers = [random.randint(1,100) for i in range(1000)]
lp = LineProfiler()
lp_wrapper = lp(do_stuff)
lp_wrapper(numbers)
lp.print_stats()

输出:

Timer unit: 1e-06 s

Total time: 0.000649 s
File: <ipython-input-2-2e060b054fea>
Function: do_stuff at line 4

Line #      Hits         Time  Per Hit   % Time  Line Contents
==============================================================
     4                                           def do_stuff(numbers):
     5         1           10     10.0      1.5      s = sum(numbers)
     6         1          186    186.0     28.7      l = [numbers[i]/43 for i in range(len(numbers))]
     7         1          453    453.0     69.8      m = ['hello'+str(numbers[i]) for i in range(len(numbers))]

向配置文件添加附加功能

此外，您还可以添加要分析的其他功能。例如，如果您有第二个 calling 函数并且您只包装了 calling 函数，您将只能看到 calling 的配置文件结果功能。

from line_profiler import LineProfiler
import random

def do_other_stuff(numbers):
    s = sum(numbers)

def do_stuff(numbers):
    do_other_stuff(numbers)
    l = [numbers[i]/43 for i in range(len(numbers))]
    m = ['hello'+str(numbers[i]) for i in range(len(numbers))]

numbers = [random.randint(1,100) for i in range(1000)]
lp = LineProfiler()
lp_wrapper = lp(do_stuff)
lp_wrapper(numbers)
lp.print_stats()

以上只会为调用函数产生以下配置文件输出:

Timer unit: 1e-06 s

Total time: 0.000773 s
File: <ipython-input-3-ec0394d0a501>
Function: do_stuff at line 7

Line #      Hits         Time  Per Hit   % Time  Line Contents
==============================================================
     7                                           def do_stuff(numbers):
     8         1           11     11.0      1.4      do_other_stuff(numbers)
     9         1          236    236.0     30.5      l = [numbers[i]/43 for i in range(len(numbers))]
    10         1          526    526.0     68.0      m = ['hello'+str(numbers[i]) for i in range(len(numbers))]

在这种情况下，您可以像这样将附加的 调用 函数添加到配置文件中:

from line_profiler import LineProfiler
import random

def do_other_stuff(numbers):
    s = sum(numbers)

def do_stuff(numbers):
    do_other_stuff(numbers)
    l = [numbers[i]/43 for i in range(len(numbers))]
    m = ['hello'+str(numbers[i]) for i in range(len(numbers))]

numbers = [random.randint(1,100) for i in range(1000)]
lp = LineProfiler()
lp.add_function(do_other_stuff)   # add additional function to profile
lp_wrapper = lp(do_stuff)
lp_wrapper(numbers)
lp.print_stats()

输出:

Timer unit: 1e-06 s

Total time: 9e-06 s
File: <ipython-input-4-dae73707787c>
Function: do_other_stuff at line 4

Line #      Hits         Time  Per Hit   % Time  Line Contents
==============================================================
     4                                           def do_other_stuff(numbers):
     5         1            9      9.0    100.0      s = sum(numbers)

Total time: 0.000694 s
File: <ipython-input-4-dae73707787c>
Function: do_stuff at line 7

Line #      Hits         Time  Per Hit   % Time  Line Contents
==============================================================
     7                                           def do_stuff(numbers):
     8         1           12     12.0      1.7      do_other_stuff(numbers)
     9         1          208    208.0     30.0      l = [numbers[i]/43 for i in range(len(numbers))]
    10         1          474    474.0     68.3      m = ['hello'+str(numbers[i]) for i in range(len(numbers))]

注意:以这种方式将函数添加到配置文件不需要更改已分析的代码(即，无需添加 @profile 装饰器)。