Datetimes – basic
Datetime
from datetime import datetime black_monday = datetim(1987, 10, 19) > datetime.datetime(1987, 10, 19, 0, 0)
Current Datetime
from datetime import datetime datetime.now()
Datetime from a string
black_monday_str = "Monday, October 19, 1987, 9:30 am" format_str = "%A, %B %d, %Y, %I:%M %p" datetime.datetime.strptime(black_monday_str, format_str) > datetime.datetime(1987, 10, 19, 9, 30)
Year: %y ... 01-99 %Y ... 0000-9999 Month : %b ... Jan-Dec %B ... January-December %m ... 01-12 Day : %d ... 01-31 Weekday : %a ... Sun-Sat %A ... Sunday-Saturday %w ... 0-6 Hour : %H ... 00-23 %I ... 00-12 Seconds : %S ... 00-59 Microseconds : %f ... 000000-999999 AM/PM : %p
"1937-05-10" --> "%Y-%m-%d" "Friday, 19 May 01" --> "%A, %d %B %y"
String from Datetime
great_depression = datetime.datetime(1929, 10, 29) great_depression.strftime("%a, %b %d, %Y") > "Tue, Oct 29, 1929"
Datetimes – working with
Datetime attributes
# March 10, 2000 Tech Bubble Crash tech_bubble = datetime(2000, 3, 10) # year yr = tech_bubble.year # month mth = tech_bubble.month # day day = tech_bubble.day print(f"Year: {yr}, Month: {mth}, Day: {day}") > Year: 2000, Month: 3, Day: 10
Comparing datetime
from datetime import datetime lehman = datetime.datetime(2008, 9, 15, 0, 0) morgan_stanley = datetime.datetime(2008, 9, 22, 0, 0) tarp = datetime.datetime(2008, 10, 3, 0, 0) # Lehman Brothers before Morgan Stanley? lehman_first = lehman < morgan_stanley print(f"It is {lehman_first} that Lehman Brothers declared bankruptcy first.") > It is True that Lehman Brothers declared bankruptcy first. # Goldman Sachs after TARP? tarp_first = goldman_sachs > tarp print(f"It is {tarp_first} that TARP was approved first.") It is False that TARP was approved first. # Goldman Sachs and Morgan Stanley same day? same_time = goldman_sachs == morgan_stanley print(f"It is {same_time} that Morgan Stanley and Goldman Sachs acted simultaneously") It is True that Morgan Stanley and Goldman Sachs acted simultaneously
Datetime calculation
from datetime import datetime, timedelta # TARP passed Oct 3 2008 tarp = datetime(2008, 10, 3) # Seven days before TARP week_before = tarp - timedelta(days = 7) # Print week_before print(week_before) > 2008-09-26 00:00:00 # One week after TARP week_after = tarp + timedelta(weeks = 1) # Print week_after print(week_after) > 2008-10-10 00:00:00 # One year after TARP year_after = tarp + timedelta(weeks = 52) # Print year_after print(year_after) > 2009-10-02 00:00:00