Tutorial Example

Calculate the Execution Time of a Python Program – A Step Guide – Python Tutorial

Sometimes, we need to evaluate the performance of a python script, we have to calculate the run or execution time a python program. In this tutorial, we will introduce you some ways.

In order to get the time spent by python script, you should get the end time and the start time.

Method 1: Use python datetime model

Here is an example:

import datetime
import time

starttime = datetime.datetime.now()

#long running
for i in range(3):
    time.sleep(1)
    

endtime = datetime.datetime.now()

t = (endtime - starttime).seconds
print(t)

Run this code, we will find this python script takes 3 seconds.

However, you should notice: if the time spent is less than 1 senconds, you will get o sencond.

Method 2: Use python time.time() function

Here is an example:

import time

starttime = time.time()

#long running
for i in range(3):
    time.sleep(0.1)
    

endtime = time.time()

t = endtime - starttime
print(t)

Run this code, you may get 0.31941890716552734 seconds.

Method 3: Use python time.clock() function

Here is an example:

import time

starttime = time.clock()

#long running
for i in range(3):
    time.sleep(0.1)
    

endtime = time.clock()

t = endtime - starttime
print(t)

Run this code, you may get 0.3198977 seconds.

The differences among these three methods

The datetime and time.time() will calculate the cpu time spent by other applications. However, time.clock() only calculate the time spent by this python script.