PyPI - Datetime

PyPI for Python 3.7

import datetime

https://docs.python.org/3.7/library/datetime.html

timedelta Object

https://docs.python.org/3.7/library/datetime.html#timedelta-objects

Constructor:

datetime.timedelta(days=0, seconds=0, microseconds=0, milliseconds=0, minutes=0, hours=0, weeks=0)

It also has a lot of operations. See the Documents for detail.

date Object

https://docs.python.org/3.7/library/datetime.html#date-objects

Datetime object is a combination of a date and a time. I like to use datetime object instead.

datetime Object

https://docs.python.org/3.7/library/datetime.html#datetime-objects

Constructor:

• datetime.datetime(year, month, day, hour=0, minute=0, second=0, microsecond=0, tzinfo=None, *, fold=0)
• datetime.datetime.fromtimestamp(timestamp, tz=None)，By timestamp
• datetime.datetime.combine(date, time, tzinfo)，Combine date object and time object
• datetime.datetime.strptime(date_string, format)，By string and format

Ordinal Date is the proleptic Gregorian ordinal of the date. It is the count from 0001-01-01, just like timestamp.

Instance methods:

(Notice: a is the name of a exist datetime object)

• a.replace(), Return a datetime with the same attributes, except for those attributes given new values.
• a.astimezone(), Return a datetime object with the timezone you give.
• a.timetuple(), Return a tuple. You can pick up what you need by index or others.
• a.toordinal(), Return the ordinal.
• a.timestamp(), Return the timestamp.
• a.strftime(format), Return the format string.

timezone Object

https://docs.python.org/3.7/library/datetime.html#timezone-objects

• datetime.timezone(offset), The offset attribute must be timedelta.

String format:

(strftime --> string from time. strptime())

https://docs.python.org/3.7/library/datetime.html#strftime-and-strptime-behavior

Directive	Tips	Meaning	Example
%Y	Year	4 bits Year	0001, 0002,..., 2019
%m	Month	1/2 bits Month	01, 02, ..., 12
%d	Day	1/2 bits Day	01, 02, ..., 31
%H	Hour	2 bits Hour	00, 01, ..., 23
%M	Minute	2 bits Minute	00, 01, ..., 59
%S	Second	2 bits Second	00, 01, ..., 59
%w	Week	1 bit, 0 for Sun. and 6 is Sat.	0, 1, ..., 6