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Questions tagged [timeit]

A Python built-in module for measuring execution time of small code snippets.

A Python built-in module for measuring execution time of small code snippets. It provides a Timer class which can be used to measure execution times.

According to the documentation, it "avoids a number of common traps for measuring execution times".

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How to measure elapsed time in Python?

What I want is to start counting time somewhere in my code and then get the passed time, to measure the time it took to execute few function. I think I'm using the timeit module wrong, but the docs are just confusing for me. import timeit start =…
gilbert8
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How to use timeit module

I understand the concept of what timeit does but I am not sure how to implement it in my code. How can I compare two functions, say insertion_sort and tim_sort, with timeit?
Neemaximo
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Creating an empty list in Python

What is the best way to create a new empty list in Python? l = [] or l = list() I am asking this because of two reasons: Technical reasons, as to which is faster. (creating a class causes overhead?) Code readability - which one is the standard…
user225312
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How can I time a code segment for testing performance with Pythons timeit?

I've a python script which works just as it should, but I need to write the execution time. I've googled that I should use timeit but I can't seem to get it to work. My Python script looks like this: import sys import getopt import timeit import…
Emil Devantie Brockdorff
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Why is it slower to iterate over a small string than a small list?

I was playing around with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time. >>>…
Sunjay Varma
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Getting "global name 'foo' is not defined" with Python's timeit

I'm trying to find out how much time it takes to execute a Python statement, so I looked online and found that the standard library provides a module called timeit that purports to do exactly that: import timeit def foo(): # ... contains code I…
Kyle Cronin
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timeit versus timing decorator

I'm trying to time some code. First I used a timing decorator: #!/usr/bin/env python import time from itertools import izip from random import shuffle def timing_val(func): def wrapper(*arg, **kw): '''source:…
unutbu
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Measure website load time with Python requests

I'm trying to build a tool for testing the delay of my internet connection, more specifically web site load times. I thought of using the python requests module for the loading part. Problem is, it's got no built-in functionality to measure the time…
cookM
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accurately measure time python function takes

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…
hoju
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What unit of time does timeit return?

I don't know how to interpret the output from Python's timeit.timeit() function. My code is as follows: import timeit setup = """ import pydash list_of_objs = [ {}, {'a': 1, 'b': 2, 0: 0}, {'a': 1, 'c': 1, 'p': lambda x:…
nivix zixer
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List comprehension vs generator expression's weird timeit results?

I was answering this question, I preferred generator expression here and used this, which I thought would be faster as generator doesn't need to create the whole list first: >>> lis=[['a','b','c'],['d','e','f']] >>> 'd' in (y for x in lis for y in…
Ashwini Chaudhary
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How can I capture return value with Python timeit module?

Im running several machine learning algorithms with sklearn in a for loop and want to see how long each of them takes. The problem is I also need to return a value and DONT want to have to run it more than once because each algorithm takes so long.…
Leon
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Why is if True slower than if 1?

Why is if True slower than if 1 in Python? Shouldn't if True be faster than if 1? I was trying to learn the timeit module. Starting with the basics, I tried these: >>> def test1(): ... if True: ... return 1 ... else: ... …
thiruvenkadam
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When should I ever use file.read() or file.readlines()?

I noticed that if I iterate over a file that I opened, it is much faster to iterate over it without "read"-ing it. i.e. l = open('file','r') for line in l: pass (or code) is much faster than l = open('file','r') for line in l.read() /…
Maverick Meerkat
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Can you capture the output of ipython's magic methods? (timeit)

I want to capture and plot the results from 5 or so timeit calls with logarithmically increasing sizes of N to show how methodX() scales with input. So far I have tried: output = %timeit -r 10 results = methodX(N) It does not work... Can't find…
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