All the IPython Notebooks in Python Date Time Module lecture series by Dr. Milaan Parmar are available @ GitHub
In this article, we will explore time module in detail. We will learn to use different time-related functions defined in the time module with the help of examples.
Python has a module named time to handle time-related tasks. To use functions defined in the module, we need to import the module first. Here's how:
import time
Here are commonly used time-related functions.
time.time()¶The time() function returns the number of seconds passed since epoch.
For Unix system, January 1, 1970, 00:00:00 at UTC is epoch (the point where time begins).
import time
seconds = time.time()
print("Seconds since epoch =", seconds)
# When you run the program, the output will be something like below:
Seconds since epoch = 1624370297.5828025
time.ctime()¶The time.ctime() function takes seconds passed since epoch as an argument and returns a string representing local time.
import time
# seconds passed since epoch
seconds = 1545925769.9618232
local_time = time.ctime(seconds)
print("Local time:", local_time)
# When you run the program, the output will be something like below:
Local time: Thu Dec 27 21:19:29 2018
time.sleep()¶The sleep() function suspends (delays) execution of the current thread for the given number of seconds.
import time
print("This is printed immediately.")
time.sleep(2.4)
print("This is printed after 2.4 seconds.")
# When you run the program, the output will be something like below:
This is printed immediately. This is printed after 2.4 seconds.
To learn more, visit: Python sleep().
Before we talk about other time-related functions, let's explore time.struct_time class in brief.
time.struct_time Class¶Several functions in the time module such as gmtime(), asctime() etc. either take time.struct_time object as an argument or return it.
Here's an example of time.struct_time object.
time.struct_time(tm_year=2018, tm_mon=12, tm_mday=27,
tm_hour=6, tm_min=35, tm_sec=17,
tm_wday=3, tm_yday=361, tm_isdst=0)
| Index | Attribute | Values |
|---|---|---|
| 0 | tm_year | 0000, ...., 2018, ..., 9999 |
| 1 | tm_mon | 1, 2, ..., 12 |
| 2 | tm_mday | 1, 2, ..., 31 |
| 3 | tm_hour | 0, 1, ..., 23 |
| 4 | tm_min | 0, 1, ..., 59 |
| 5 | tm_sec | 0, 1, ..., 61 |
| 6 | tm_wday | 0, 1, ..., 6; Monday is 0 |
| 7 | tm_yday | 1, 2, ..., 366 |
| 8 | tm_isdst | 0, 1 or -1 |
The values (elements) of the time.struct_time object are accessible using both indices and attributes.
time.localtime()¶The localtime() function takes the number of seconds passed since epoch as an argument and returns struct_time in local time.
import time
result = time.localtime(1545925769)
print("result:", result)
print("\nyear:", result.tm_year)
print("tm_hour:", result.tm_hour)
# When you run the program, the output will be like below:
result: time.struct_time(tm_year=2018, tm_mon=12, tm_mday=27, tm_hour=21, tm_min=19, tm_sec=29, tm_wday=3, tm_yday=361, tm_isdst=0) year: 2018 tm_hour: 21
Note: If no argument or
Noneis passed tolocaltime(), the value returned bytime()is used.
time.gmtime()¶The gmtime() function takes the number of seconds passed since epoch as an argument and returns struct_time in UTC.
import time
result = time.gmtime(1545925769)
print("result:", result)
print("\nyear:", result.tm_year)
print("tm_hour:", result.tm_hour)
# When you run the program, the output will be like below:
result: time.struct_time(tm_year=2018, tm_mon=12, tm_mday=27, tm_hour=15, tm_min=49, tm_sec=29, tm_wday=3, tm_yday=361, tm_isdst=0) year: 2018 tm_hour: 15
Note: If no argument or
Noneis passed togmtime(), the value returned bytime()is used.
time.mktime()¶The mktime() function takes struct_time (or a tuple containing 9 elements corresponding to struct_time) as an argument and returns the seconds passed since epoch in local time. Basically, it's the inverse function of localtime().
import time
t = (2018, 12, 28, 8, 44, 4, 4, 362, 0)
local_time = time.mktime(t)
print("Local time:", local_time)
# When you run the program, the output will be something like below:
Local time: 1545966844.0
The example below shows how mktime() and localtime() are related.
import time
seconds = 1545925769
# returns struct_time
t = time.localtime(seconds)
print("t1: ", t)
# returns seconds from struct_time
s = time.mktime(t)
print("\s:", seconds)
# When you run the program, the output will be like below:
t1: time.struct_time(tm_year=2018, tm_mon=12, tm_mday=27, tm_hour=21, tm_min=19, tm_sec=29, tm_wday=3, tm_yday=361, tm_isdst=0) \s: 1545925769
time.asctime()¶The asctime() function takes struct_time (or a tuple containing 9 elements corresponding to struct_time) as an argument and returns a string representing it. Here's an example:
import time
t = (2018, 12, 28, 8, 44, 4, 4, 362, 0)
result = time.asctime(t)
print("Result:", result)
# When you run the program, the output will be like below:
Result: Fri Dec 28 08:44:04 2018
time.strftime()¶The strftime() function takes struct_time (or tuple corresponding to it) as an argument and returns a string representing it based on the format code used. For example,
import time
named_tuple = time.localtime() # get struct_time
time_string = time.strftime("%m/%d/%Y, %H:%M:%S", named_tuple)
print(time_string)
# When you run the program, the output will be something like below:
06/22/2021, 19:28:41
Note: Here,
%Y,,%m,%d,%Hetc. are format codes.
| Directive | Meaning | Example |
|---|---|---|
%Y |
year | [0001,..., 2018, 2019,..., 9999] |
%m |
month | [01, 02, ..., 11, 12] |
%d |
day | [01, 02, ..., 30, 31] |
%H |
hour | [00, 01, ..., 22, 23] |
%M |
minute | [00, 01, ..., 58, 59] |
%S |
second | [00, 01, ..., 58, 61] |
To learn more, visit: time.strftime().
time.strptime()¶The strptime() function parses a string representing time and returns struct_time.
import time
time_string = "21 June, 2018"
result = time.strptime(time_string, "%d %B, %Y")
print(result)
# When you run the program, the output will be like below:
time.struct_time(tm_year=2018, tm_mon=6, tm_mday=21, tm_hour=0, tm_min=0, tm_sec=0, tm_wday=3, tm_yday=172, tm_isdst=-1)