问题
I am trying to figure out how I can run Python's line_profiler to get the line by line execution times in the format given in the answer to this question.
I installed the module and am calling its LineProfiler object as below but the output I get is just a single time and not a line by line summary.
Any ideas? Furthermore, how can I get the time for the numbers = [random.randint(1,100) for i in range(1000)] line that is outside any function?
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)]
profile = LineProfiler(do_stuff(numbers))
profile.print_stats()
[] Timer unit: 3.20721e-07 s
回答1:
The line_profiler test cases (found on GitHub) have an example of how to generate profile data from within a Python script. You have to wrap the function that you want to profile and then call the wrapper passing any desired function arguments.
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()
Output:
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))]
Adding Additional Functions to Profile
Also, you can add additional functions to be profiled as well. For example, if you had a second called function and you only wrap the calling function, you'll only see the profile results from the calling function.
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()
The above would only produce the following profile output for the calling function:
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))]
In this case, you can add the additional called function to profile like this:
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()
Output:
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))]
NOTE: Adding functions to profile in this way does not require changes to the profiled code (i.e., no need to add @profile decorators).
回答2:
As described in the documentation:
in your script, you can decorate any function you want to profile with @profile
You want to decorate your do_stuff function with @profile and then run
kernprof.py -v -l script_to_profile.py
to get the annotated output printed to your terminal. The profile will also be written to script_to_profile.py.lprof and you can re-create the output later with
python -m line_profiler script_to_profile.py.lprof
来源：https://stackoverflow.com/questions/22328183/python-line-profiler-code-example