I'm running some experiments and I need to precisely measure participants' response time to questions. I know there are some commercial software, but I was wondering if I can do this with Python. Does python provides suitable functionality to measure the response time in millisecond unit?
Thank you,
Joon
Just do something like this:
from time import time
starttime = time()
askQuestion()
timetaken = time() - starttime
You could measure the execution time between the options displayed and the input received.
http://docs.python.org/library/timeit.html
def whatYouWantToMeasure():
pass
if __name__=='__main__':
from timeit import Timer
t = Timer("whatYouWantToMeasure()", "from __main__ import test")
print t.timeit(number=1)
You might want to look at the timeit module.
import timeit
Related
I am writing this program and I want to round the time that gets printed off to the tens place.
from timeit import default_timer
start= default_timer()
#This is where i have a bunch of other code that isn't relavant
duration = default_timer()-start
print (duration)
I tried to use round(duration, 2) before I printed it and that didn't work. I just don't really know how to round it. There's probably a simple answer but I couldn't figure it out. Thanks!!
Duplicate of this question. This is one answer provided in that link:
from timeit import default_timer
import time
start= default_timer()
time.sleep(2) # Insert your code here.
duration = default_timer()-start
print("{0:.2f}".format(duration))
I want to calculate the execution time of code of various languages such as java, python, javascript. How to get the execution time of these codes. Is there any tool available in python packages or any other to calculate the execution time by passing the file(any file java or python) path. Please share your suggestion.
I am aware of getting execution time by using time module in python code. How to execute Javascript and java codes in python and get the execution time in common function.
I tried in below method.
import time
def get_exectime(file_path): # pass path of any file python,java,javascript, html, shell
start_time=time.time()
# execute the file given here. How to execute all file types here?
end_time=time.time()
exec_time=end_time-start_time
print(exec_time)
Is there any other method available to achieve this?
You can do that using the time module:
import time
start_time = time.time()
# your code
end_time = time.time()
print("Total execution time: {} seconds".format(end_time - start_time))
Contrary to other answers, I suggest using timeit, which was designed with the very purpose of measuring execution times in mind, and can also be used as a standalone tool: https://docs.python.org/3/library/timeit.html
It will give you not only the real time of execution, but also CPU time used, which is not necessarily the same thing.
import time
start_time = time.time()
#code here
print("--- %s seconds ---" % (time.time() - start_time))
I think you might need time module. This is the simplest way to measure execution time inn python. Take a look at my example.
import time
start_time = time.time()
a=1
for i in range(10000):
a=a+1
end_time = time.time()
total_time = end_time-start_time
print("Execution time in seconds: %s ",total_time)
Output:
Execution time in seconds: %s 0.0038547515869140625
>>>
First install "humanfriendly" package in python by opening Command Prompt (CMD) as administrator and type -
pip install humanfriendly
Code:
from humanfriendly import format_timespan
import time
begin_time = time.time()
# Put your code here
end_time = time.time() - begin_time
print("Total execution time: ", format_timespan(end_time))
Output:
Is there a simple way to time a Python program's execution?
clarification: Entire programs
Use timeit:
This module provides a simple way to time small bits of Python code. It has both command line as well as callable interfaces. It avoids a number of common traps for measuring execution times.
You'll need a python statement in a string; if you have a main function in your code, you could use it like this:
>>> from timeit import Timer
>>> timer = Timer('main()', 'from yourmodule import main')
>>> print timer.timeit()
The second string provides the setup, the environment for the first statement to be timed in. The second part is not being timed, and is intended for setting the stage as it were. The first string is then run through it's paces; by default a million times, to get accurate timings.
If you need more detail as to where things are slow, use one of the python profilers:
A profiler is a program that describes the run time performance of a program, providing a variety of statistics.
The easiest way to run this is by using the cProfile module from the command line:
$ python -m cProfile yourprogram.py
You might want to use built-in profiler.
Also you might want to measure function's running time by using following simple decorator:
import time
def myprof(func):
def wrapping_fun(*args):
start = time.clock()
result = func(*args)
end = time.clock()
print 'Run time of %s is %4.2fs' % (func.__name__, (end - start))
return result
return wrapping_fun
Usage:
#myprof
def myfun():
# function body
If you're on Linux/Unix/POSIX-combatible platform just use time. This way you won't interfere with you script and won't slow it down with unnecessarily detailed (for you) profiling. Naturally, you can use it for pretty much anything, not just Python scripts.
For snippets use the timeit module.
For entire programs use the cProfile module.
Use timeit
>>> import timeit
>>> t = timeit.Timer(stmt="lst = ['c'] * 100")
>>> print t.timeit()
1.10580182076
>>> t = timeit.Timer(stmt="lst = ['c' for x in xrange(100)]")
>>> print t.timeit()
7.66900897026
I would like to know that how much time a particular function has spent during the duration of the program which involves recursion, what is the best way of doing it?
Thank you
The best way would be to run some benchmark tests (to test individual functions) or Profiling (to test an entire application/program). Python comes with built-in Profilers.
Alternatively, you could go back to the very basics by simply setting a start time at the beginning of the program, and, at the end of the program, subtracting the current time from the start time. This is basically very simple Benchmarking.
Here is an implementation from the an answer from the linked question:
import time
start = time.time()
do_long_code()
print "it took", time.time() - start, "seconds."
Python has something for benchmarking included in its standard library, as well.
From the example give on the page:
def test():
"Time me"
L = []
for i in range(100):
L.append(i)
if __name__=='__main__':
from timeit import Timer
t = Timer("test()", "from __main__ import test")
print t.timeit()
Use the profiler!
python -m cProfile -o prof yourscript.py
runsnake prof
runsnake is a nice tool for looking at the profiling output. You can of course use other tools.
More on the Profiler here: http://docs.python.org/library/profile.html
I need to measure the time certain parts of my program take (not for debugging but as a feature in the output). Accuracy is important because the total time will be a fraction of a second.
I was going to use the time module when I came across timeit, which claims to avoid a number of common traps for measuring execution times. Unfortunately it has an awful interface, taking a string as input which it then eval's.
So, do I need to use this module to measure time accurately, or will time suffice? And what are the pitfalls it refers to?
Thanks
According to the Python documentation, it has to do with the accuracy of the time function in different operating systems:
The default timer function is platform
dependent. On Windows, time.clock()
has microsecond granularity but
time.time()‘s granularity is 1/60th of
a second; on Unix, time.clock() has
1/100th of a second granularity and
time.time() is much more precise. On
either platform, the default timer
functions measure wall clock time, not
the CPU time. This means that other
processes running on the same computer
may interfere with the timing ... On Unix, you can
use time.clock() to measure CPU time.
To pull directly from timeit.py's code:
if sys.platform == "win32":
# On Windows, the best timer is time.clock()
default_timer = time.clock
else:
# On most other platforms the best timer is time.time()
default_timer = time.time
In addition, it deals directly with setting up the runtime code for you. If you use time you have to do it yourself. This, of course saves you time
Timeit's setup:
def inner(_it, _timer):
#Your setup code
%(setup)s
_t0 = _timer()
for _i in _it:
#The code you want to time
%(stmt)s
_t1 = _timer()
return _t1 - _t0
Python 3:
Since Python 3.3 you can use time.perf_counter() (system-wide timing) or time.process_time() (process-wide timing), just the way you used to use time.clock():
from time import process_time
t = process_time()
#do some stuff
elapsed_time = process_time() - t
The new function process_time will not include time elapsed during sleep.
Python 3.7+:
Since Python 3.7 you can also use process_time_ns() which is similar to process_time()but returns time in nanoseconds.
You could build a timing context (see PEP 343) to measure blocks of code pretty easily.
from __future__ import with_statement
import time
class Timer(object):
def __enter__(self):
self.__start = time.time()
def __exit__(self, type, value, traceback):
# Error handling here
self.__finish = time.time()
def duration_in_seconds(self):
return self.__finish - self.__start
timer = Timer()
with timer:
# Whatever you want to measure goes here
time.sleep(2)
print timer.duration_in_seconds()
The timeit module looks like it's designed for doing performance testing of algorithms, rather than as simple monitoring of an application. Your best option is probably to use the time module, call time.time() at the beginning and end of the segment you're interested in, and subtract the two numbers. Be aware that the number you get may have many more decimal places than the actual resolution of the system timer.
I was annoyed too by the awful interface of timeit so i made a library for this, check it out its trivial to use
from pythonbenchmark import compare, measure
import time
a,b,c,d,e = 10,10,10,10,10
something = [a,b,c,d,e]
def myFunction(something):
time.sleep(0.4)
def myOptimizedFunction(something):
time.sleep(0.2)
# comparing test
compare(myFunction, myOptimizedFunction, 10, input)
# without input
compare(myFunction, myOptimizedFunction, 100)
https://github.com/Karlheinzniebuhr/pythonbenchmark
Have you reviewed the functionality provided profile or cProfile?
http://docs.python.org/library/profile.html
This provides much more detailed information than just printing the time before and after a function call. Maybe worth a look...
The documentation also mentions that time.clock() and time.time() have different resolution depending on platform. On Unix, time.clock() measures CPU time as opposed to wall clock time.
timeit also disables garbage collection when running the tests, which is probably not what you want for production code.
I find that time.time() suffices for most purposes.
From Python 2.6 on timeit is not limited to input string anymore. Citing the documentation:
Changed in version 2.6: The stmt and setup parameters can now also take objects that are callable without arguments. This will embed calls to them in a timer function that will then be executed by timeit(). Note that the timing overhead is a little larger in this case because of the extra function calls.