Python3 date and time

Python3 date and time

Python programs can handle dates and times in many ways, and converting date formats is a common feature.

Python provides a time and calendar module that can be used to format dates and times.

The interval is a small number of floating points in seconds.

Each timestamp is expressed in terms of how long it has been since midnight (calendar) on January 1, 1970.

There are many functions under Python's time module that convert common date formats. As the function time.time() is used to get the current timestamp, the following example:

#!/usr/bin/python3




import time;  # 引入time模块

ticks = time.time()
print ("当前时间戳为:", ticks)

The above example output results:

当前时间戳为: 1459996086.7115328

Timestamp units are best suited for date operations. B ut the dates before 1970 cannot be expressed in this way. Too distant a date, UNIX and Windows only support until 2038.

What is a time group?

Many Python functions process time with 9 sets of numbers assembled in one meta:

The above is struct_time the two metagroups. This structure has the following properties:

Gets the current time

Switch from the time drop that returns floats to the time group, as long as the floats are passed to a function such as localtime.

#!/usr/bin/python3
import time

localtime = time.localtime(time.time())
print ("本地时间为 :", localtime)

The above example output results:

本地时间为 : time.struct_time(tm_year=2016, tm_mon=4, tm_mday=7, tm_hour=10, tm_min=28, tm_sec=49, tm_wday=3, tm_yday=98, tm_isdst=0)

Gets the time it was formatted

You can choose from a variety of formats depending on your needs, but the simplest function to get readable time patterns is asctime():

#!/usr/bin/python3
import time

localtime = time.asctime( time.localtime(time.time()) )
print ("本地时间为 :", localtime)

The above example output results:

本地时间为 : Thu Apr  7 10:29:13 2020

Format the date

We can format the date using the strftime method of the time module:

time.strftime(format[, t])

#!/usr/bin/python3
import time

# 格式化成2020-03-20 11:45:39形式
print
    (time.strftime("%Y-%m-%d %H:%M:%S", time
        .localtime()))

# 格式化成Sat Mar 28 22:24:24 2020形式
print 
            (time.strftime("%a %b %d %H:%M:%S %Y", time.
                localtime()))  

# 将格式字符串转换为时间戳
a = "Sat Mar 28 22:24:24 2020"

                    print (time.mktime(time.
                        strptime(a,"%a %b %d %H:%M:%S %Y")))               

The above example output results:

2020-04-07 10:29:46
Thu Apr 07 10:29:46 
20201459175064.0

Time date formatting symbol in Python:

• %y Two-digit year (00-99)
• %Y four-digit year (000-9999)
• %m month (01-12)
• One day in %d month (0-31)
• %H 24 hours (0-23)
• %I 12 hours (01-12)
• %M minutes (00 s 59)
• %S Seconds (00-59)
• %a Local simplified week name
• %A local full week name
• %b Local simplified month name
• %B Local full month name
• %c Local corresponding date and time represents
• %j Day of the Year (001-366)
• %p Local A.M. or P.M. equivalent
• %U The number of weeks of the year (00-53) Sunday is the beginning of the week
• %w week (0-6), Sunday is the beginning of the week
• %W The number of weeks of the year (00-53) Monday is the beginning of the week
• %x locally represented by the corresponding date
• %X is locally represented by the appropriate time
• The name of the current time zone for %Z
• %% % sign itself

Get a calendar for a month

The Calendar module has a wide range of methods for working with annual and monthly calendars, such as printing monthly calendars for a month:

#!/usr/bin/python3

import calendar
cal = calendar.month(2020, 9)
print ("以下输出2020年9月份的日历:")
print (cal)

The above example output results:

以下输出2020年9月份的日历:    
    September 2020
Mo Tu We Th Fr Sa Su             
            1  2  3 
4  5  6  7  8  9  10
11 12 13 14 15 16 17
18 19 20 21 22 23 24
25 26 27 28 29 30 31

Time module

The Time module contains the following built-in functions, both in the time-processing phase and in the conversion time format:

>>> import time
>>> print ("time.altzone %d " % time.altzone)
time.altzone -28800 

>>> import time
>>> t = time.localtime()
>>> print ("time.asctime(t): %s " % time.asctime(t))
time.asctime(t): Thu Apr  7 10:36:20 2016 

>>> import time
>>> print ("time.ctime() : %s" % time.ctime())
time.ctime() : Thu Apr  7 10:51:58 2016

>>> import time
>>> print ("gmtime :", time.gmtime(1455508609.34375))
gmtime : time.struct_time(tm_year=2016, tm_mon=2, tm_mday=15, tm_hour=3, tm_min=56, tm_sec=49, tm_wday=0, tm_yday=46, tm_isdst=0)

>>> import time
>>> print ("localtime(): ", time.localtime(1455508609.34375))
localtime():  time.struct_time(tm_year=2016, tm_mon=2, tm_mday=15, tm_hour=11, tm_min=56, tm_sec=49, tm_wday=0, tm_yday=46, tm_isdst=0)

#!/usr/bin/python3
import time

print ("Start : %s" % time.ctime())
time.sleep( 5 )
print ("End : %s" % time.ctime())

>>> import time
>>> print (time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
2016-04-07 11:18:05

>>> import time
>>> struct_time = time.strptime("30 Nov 00", "%d %b %y")
>>> print ("返回元组: ", struct_time)
返回元组:  time.struct_time(tm_year=2000, tm_mon=11, tm_mday=30, tm_hour=0, tm_min=0, tm_sec=0, tm_wday=3, tm_yday=335, tm_isdst=-1)

>>> import time
>>> print(time.time())
1459999336.1963577

The Time module contains two very important properties:

Calendar module

The functions of this module are calendar-related, such as printing a month's character calendar.

Monday is the default first day of the week, and Sunday is the default last day. C hanging the settings requires calling the calendar.setfirstweekday() function. The module contains the following built-in functions:

Other related modules and functions

In Python, other modules that handle dates and times are:

• Time module
• Datetime module