Python3 Time Module

Python3 the time module

Time & datetime & Calendar

I. Overview

Python provides many ways to handle dates and times, and converting date formats is a common feature.

Time tuples : Many Python functions use a single element to assemble 9 sets of digital processing time.

Field	Property	Value
4-digit number of years	Tm_year	2017
Month	Tm_mon	1 to 12
Day	Tm_mday	1 to 31
Hours	Tm_hour	0 to 23
Minutes	Tm_min	0 to 59
Seconds	Tm_sec	0 to 61 (60 or 61 is run seconds)
The first day of the week	Tm_wday	0 to 6 (0 is Monday)
The first day of the year	Tm_yday	1 to 366, the day ordinal of a year
Daylight saving time	Tm_isdst	Is daylight saving time, the value is 1 o'clock daylight saving time, the value is 0 o'clock is not daylight saving time, default is-1

#从返回浮点数的时间辍方式向时间元组转换, simply pass the floating-point number to a function such as localtime

>>> Print (Time.localtime (Time.time ()))

Time.struct_time (tm_year=2018, tm_mon=5, tm_mday=18, tm_hour=18, tm_min=40, tm_sec=58, tm_wday=4, tm_yday=138, tm_ isdst=0)
#当前时间为: 2018, May, 18th, 18 o'clock, 40 minutes, 58 seconds, Thursday, 138 days of the year, not daylight saving time

python Medium Time date formatting symbols:

1	%y	Two-digit year representation (00-99)
2	%Y	A four-digit year representation (000-9999)
3	%m	Month (01-12)
4	%d	Day of the Month (0-31)
5	%H	24-hour hours (0-23)
6	%I	12-hour hours (01-12)
7	%M	Number of minutes (00=59)
8	%s	Seconds (00-59)
9	%a	Local Simplified Week name
10	%A	Local Full week name
11	%b	Locally Simplified month name
12	%B	Local Full month name
13	%c	Local corresponding date representation and time representation
14	%j	Day of the Year (001-366)
15	%p	equivalent of local a.m. or p.m.
16	%u	Week of the Year (00-53) Sunday is the beginning of the week
17	%w	Week (0-6), Sunday for the beginning of the week
18	%W	Week of the Year (00-53) Monday is the beginning of the week
19	%x	Local corresponding date representation
20	%x	Local corresponding time representation
21st	%Z	The name of the current time zone
22	%%	% number itself

two. Time Module

Time-related operations, time has three kinds of means:

• Timestamp after January 1, 1970 seconds, i.e.: Time.time ()
• Formatted string 2014-11-11 11:11, i.e.: Time.strftime ('%y-%m-%d ')
• Structured time tuples include: year, day, week, etc. time.struct_time is: time.localtime ()

Time.time ()

1 2 3 4 5

Returns the timestamp of the current time (the number of floating-point seconds elapsed after the 1970 era). Timestamp units are best suited for date operations. But the dates before 1970 cannot be expressed in this way. Too far away from the date, UNIX and Windows only support to 2038 years. >>> Import Time >>> print (Time.time ()) 1459999336.1963577

　　

Time.mktime (Tupletime)

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Accepts the time tuple and returns the time suffix (the number of floating-point seconds elapsed after the 1970 era). The Python time.mktime () function performs the opposite of Gmtime (), localtime (), which receives the Struct_time object as a parameter and returns a floating-point number that represents the time in seconds. If the value entered is not a valid time, overflowerror or valueerror will be triggered. #!/usr/bin/python3 Import time t = (2016, 2, 17, 17, 3, 38, 1, 48, 0) secs = Time.mktime (t) Print ("Time.mktime (t):%f"% secs) Print ("Asctime (localtime (secs)):%s"% Time.asctime (time.localtime (secs))) The result of the above example output is: Time.mktime (t): 1455699818.000000 Asctime (localtime (secs)): Wed Feb 17 17:03:38 2016

　　

Time.gmtime ([secs])

1 2 3 4

Receives the time suffix (the number of floating-point seconds elapsed after the 1970 era) and returns the time-tuple T in Greenwich Astronomical time. Note: T.TM_ISDST is always 0 >>> 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)

　　

Time.localtime ([secs])

1 2 3 4

The Receive time suffix (the number of floating-point seconds after the 1970 era) and the time-of-day tuple T (t.tm_isdst 0 or 1, depending on whether the local time is daylight saving). >>> 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)

　　

Time.mktime (Tupletime)

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Accepts the time tuple and returns the time suffix (the number of floating-point seconds elapsed after the 1970 era). The Python time Mktime () function performs the opposite of Gmtime (), localtime (), which receives the Struct_time object as a parameter and returns a floating-point number that represents the times in seconds. If the value entered is not a valid time, overflowerror or valueerror will be triggered. #!/usr/bin/python3 Import time t = (2016, 2, 17, 17, 3, 38, 1, 48, 0) secs = Time.mktime (t) Print ("Time.mktime (t):%f"% secs) Print ("Asctime (localtime (secs)):%s"% Time.asctime (time.localtime (secs))) The result of the above example output is: Time.mktime (t): 1455699818.000000 Asctime (localtime (secs)): Wed Feb 17 17:03:38 2016

　　

Time.strftime (Fmt[,tupletime])

1 2 3 4 5

Receives a time tuple and returns the local time as a readable string, formatted as determined by the FMT. >>> Import Time >>> Print (Time.strftime ("%y-%m-%d%h:%m:%s", Time.localtime ())) 2016-04-07 11:18:05

　　

Time.strptime (str,fmt= '%a%b%d%h:%m:%s%Y ')

1 2 3 4 5

Resolves a time string to a time tuple according to the format of the FMT. >>> Import Time >>> struct_time = Time.strptime ("Nov", "%d%b%y") >>> print ("Return to Tuple:", Struct_time) Return tuples: 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)

　　

Time.altzone

1 2 3 4

Returns the number of seconds to offset the daylight saving time region in West Greenwich. If the region returns negative values in eastern Greenwich (such as Western Europe, including the UK). Available for daylight saving time enabled regions. >>> Import Time >>> print ("Time.altzone%d"% time.altzone) time.altzone-28800

　　

Time.asctime ([Tupletime])

1 2 3 4 5

Accepts a time tuple and returns a read-only string of 24 characters in the form "Tue Dec 11 18:07:14 2008" (December 11, 2008 Tuesday 18:07 14 seconds). >>> Import Time >>> t = time.localtime () >>> Print ("Time.asctime (t):%s"% time.asctime (t)) Time.asctime (t): Thu APR 7 10:36:20 2016

　　

Time.clock ()

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

The number of seconds used to calculate the floating-point count returns the current CPU time. It is more useful than time.time () to measure the time spent on different programs. #!/usr/bin/python3 Import time def procedure (): Time.sleep (2.5) # Time.clock T0 = Time.clock () Procedure () Print (Time.clock ()-T0) # Time.time T0 = Time.time () Procedure () Print (Time.time ()-T0) The result of the above example output is: 5.000000000000143e-05 2.5020556449890137

　　

Time.ctime ([secs])

1 2 3 4

function equivalent to Asctime (localtime (secs)), parameter is not given equal to Asctime () >>> Import Time >>> Print ("Time.ctime ():%s"% time.ctime ()) Time.ctime (): Thu APR 7 10:51:58 2016

　　

Time.sleep (secs)

1 2 3 4 5 6 7

Postpone the call thread's run, secs refers to the number of seconds. #!/usr/bin/python3 Import time Print ("Start:%s"% time.ctime ()) Time.sleep (5) Print ("End:%s"% time.ctime ())

　　

Time.tzset ()

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21st 22 23 24 25 26 27

Re-initializes time-related settings according to the environment variable TZ. Standard TZ environment variable format: STD offset [DST [offset [, Start[/time], End[/time]] Parameters: STD and DST: abbreviated letters of three or more times. Passed to Time.tzname. Offset: Offsets from UTC, Format: [+|-]hh[:mm[:ss]] {h=0-23, m/s=0-59}. Start[/time], End[/time]: date when DST begins to take effect. The format is m.w.d-, which represents the month, week, and date of the date. W=1 refers to the first week of the month, while W=5 refers to the last week of the month. ' Start ' and ' end ' can be in one of the following formats: Jn: Julian Day N (1 <= n <= 365). Leap Year Day (February 29) is not counted. N: Julian Day (0 <= n <= 365). Leap Year Day (February 29) counted MM.N.D: The month, week number, and date of the date. W=1 refers to the first week of the month, while W=5 refers to the last week of the month. Time: (optional) When DST begins to take effect (24-hour system). The default value is 02:00 (the local time for the specified time zone). #!/usr/bin/python3 Import time Import OS os.environ[' TZ '] = ' est+05edt,m4.1.0,m10.5.0 ' Time.tzset () Print (Time.strftime ('%x%x%Z ')) os.environ[' TZ '] = ' aest-10aedt-11,m10.5.0,m3.5.0 ' Time.tzset () Print (Time.strftime ('%x%x%Z ')) The result of the above example output is: 23:25:45 04/06/16 EDT 13:25:45 04/07/16 AEST

　　

Time.timezone

1	The attribute Time.timezone is the number of seconds (>0, Americas; <=0 most of Europe, Asia, and Africa) from Greenwich in the local time zone (daylight saving is not started).

　　

Time.tzname

1	The Time.tzname property contains a pair of different strings depending on the situation, which is the local time zone name with daylight savings, and No.

　　

Time Change chart:

Python3 Time Module