3.3. Datetime Format

3.3.1. String Format Time

>>> from datetime import datetime
>>>
>>>
>>> gagarin = datetime(1961, 4, 12, 6, 7)
>>> formatted = gagarin.strftime('%Y-%m-%d %H:%M')
>>>
>>> print(f'Gagarin launched on {formatted}')
Gagarin launched on 1961-04-12 06:07

3.3.2. Format String

>>> from datetime import datetime
>>>
>>>
>>> gagarin = datetime(1961, 4, 12, 6, 7)
>>>
>>> print(f'Gagarin launched on {gagarin:%Y-%m-%d}')
Gagarin launched on 1961-04-12
>>>
>>> print(f'Gagarin launched on {gagarin:%Y-%m-%d %H:%M}')
Gagarin launched on 1961-04-12 06:07
>>> from datetime import datetime
>>>
>>>
>>> gagarin = datetime(1961, 4, 12, 6, 7)
>>> format = '%Y-%m-%d %H:%M'
>>>
>>> print(f'Gagarin launched on {gagarin:{format}}')
Gagarin launched on 1961-04-12 06:07

3.3.3. Parameters

  • Almost any programming language has very similar date formatting parameters

  • Some minor differences like in JavaScript minutes are i, not M

Table 3.1. Date and time parsing and formatting parameters

Directive

Example

Meaning

%a

Sun, Mon, …, Sat

Weekday as locale's abbreviated name

%A

Sunday, Monday, …, Saturday (en_US)

Weekday as locale's full name

%w

0, 1, …, 6

Weekday as a decimal number, where 0 is Sunday and 6 is Saturday

%d

01, 02, …, 31

Day of the month as a zero-padded decimal number

%b

Jan, Feb, …, Dec (en_US)

Month as locale's abbreviated name

%B

January, February, …, December (en_US)

Month as locale’s full name

%m

01, 02, …, 12

Month as a zero-padded decimal number

%y

00, 01, …, 99

Year without century as a zero-padded decimal number

%Y

0001, 0002, …, 2013, 2014, …, 9998, 9999

Year with century as a decimal number

%H

00, 01, …, 23

Hour (24-hour clock) as a zero-padded decimal number

%I

01, 02, …, 12

Hour (12-hour clock) as a zero-padded decimal number

%p

AM, PM (en_US)

Locale’s equivalent of either AM or PM

%M

00, 01, …, 59

Minute as a zero-padded decimal number

%S

00, 01, …, 59

Second as a zero-padded decimal number

%f

000000, 000001, …, 999999

Microsecond as a decimal number, zero-padded on the left

%z

(empty), +0000, -0400, +1030

UTC offset in the form +HHMM or -HHMM (empty string if the object is naive)

%Z

(empty), UTC, EST, CST

Time zone name (empty string if the object is naive)

%j

001, 002, …, 366

Day of the year as a zero-padded decimal number

%U

00, 01, …, 53

Week number of the year (Sunday as the first day of the week) as a zero padded decimal number. All days in a new year preceding the first Sunday are considered to be in week 0

%W

00, 01, …, 53

Week number of the year (Monday as the first day of the week) as a decimal number. All days in a new year preceding the first Monday are considered to be in week 0

%c

Tue Aug 16 21:30:00 1988 (en_US)

Locale’s appropriate date and time representation

%x

08/16/1988 (en_US); 16.08.1988 (de_DE)

Locale’s appropriate date representation

%X

21:30:00

Locale’s appropriate time representation

%%

%

A literal % character

%G

0001, 0002, …, 2013, 2014, …, 9998, 9999

ISO 8601 year with century representing the year that contains the greater part of the ISO week (%V)

%u

1, 2, …, 7

ISO 8601 weekday as a decimal number where 1 is Monday

%V

01, 02, …, 53

ISO 8601 week as a decimal number with Monday as the first day of the week. Week 01 is the week containing Jan 4

Todo

Convert table into smaller parts, based on categories: months, day, hour etc.

3.3.4. Leading Zero

3.3.5. Assignments

Code 3.5. Solution
"""
* Assignment: Datetime Format US
* Complexity: easy
* Lines of code: 1 lines
* Time: 3 min

English:
    1. Define `result: str` with `DATA` in long US format
    2. Run doctests - all must succeed

Polish:
    1. Zdefiniuj `result: str` z `DATA` w długim formacie amerykańskim
    2. Uruchom doctesty - wszystkie muszą się powieść

Tests:
    >>> import sys; sys.tracebacklimit = 0

    >>> assert type(result) is str, \
    'Variable `result` has invalid type, must be a str'

    >>> result
    'July 21, 1969 02:56:15 AM'
"""

from datetime import datetime


DATA = datetime(1969, 7, 21, 2, 56, 15)

result = ...  # str: DATA in long US format: 'July 21, 1969 02:56:15 AM'


Code 3.6. Solution
"""
* Assignment: Datetime Format LeadingZero
* Complexity: easy
* Lines of code: 1 lines
* Time: 3 min

English:
    1. Define `result: str` with `DATA` in short US format
    2. Make sure, that hour is without leading zero
    3. Run doctests - all must succeed

Polish:
    1. Zdefiniuj `result: str` z `DATA` w długim formacie amerykańskim
    2. Upewnij się, że godzina jest bez wiodącego zera
    3. Uruchom doctesty - wszystkie muszą się powieść

Hints:
    * Use `%-I` on \*nix systems (macOS, BSD, Linux)
    * Use `%#I` on Windows

Tests:
    >>> import sys; sys.tracebacklimit = 0

    >>> assert type(result) is str, \
    'Variable `result` has invalid type, must be a str'

    >>> result
    '07/21/69 2:56 AM'
"""

from datetime import datetime


DATA = datetime(1969, 7, 21, 2, 56, 15)

result = ...  # str: DATA in short US format: '07/21/69 2:56 AM'