datetimes के साथ काम करना

इंटरमीडिएट Python फॉर फाइनेंस

Kennedy Behrman

Data Engineer, Author, Founder

Datetime attributes

now.year
now.month
now.day

2019
11
13

now.hour
now.minute
now.second

22
34
56

Datetimes की तुलना

बराबर ==

कम than <

ज़्यादा than >

Datetimes की तुलना

from datetime import datetime
asian_crisis = datetime(1997, 7, 2)
world_mini_crash = datetime(1997, 10, 27)

asian_crisis > world_mini_crash

False

asian_crisis < world_mini_crash

True

Datetimes की तुलना

asian_crisis = datetime(1997, 7, 2)
world_mini_crash = datetime(1997, 10, 27)

text = "10/27/1997"
format_str =  "%m/%d/%Y"
sell_date = datetime.strptime(text, format_str)

sell_date == world_mini_crash

True

Datetimes के बीच अंतर

<, >, या == से तुलना करें.
घटाने पर timedelta ऑब्जेक्ट मिलता है.
timedelta attributes: weeks, days, minutes, seconds, microseconds

Datetimes के बीच अंतर

delta = world_mini_crash - asian_crisis

type(delta)

datetime.timedelta

delta.days

Relative datetimes बनाना

dt

datetime.datetime(2019, 1, 14, 0, 0)

datetime(dt.year, dt.month, dt.day - 7)

datetime.datetime(2019, 1, 7, 0, 0)

datetime(dt.year, dt.month, dt.day - 15)

ValueError                                Traceback (most recent call last)
<ipython-input-28-804001f45cdb> in <module>()
-> 1 datetime(dt.year, dt.month, dt.day - 15)
ValueError: day is out of range for month

Relative datetimes बनाना

delta = world_mini_crash - asian_crisis
type(delta)

datetime.timedelta

Relative datetimes बनाना

from datetime import timedelta

offset = timedelta(weeks = 1)
offset

datetime.timedelta(7)

dt - offset

datetime.datetime(2019, 1, 7, 0, 0)

Relative datetimes बनाना

offset = timedelta(days=16)
dt - offset

datetime.datetime(2018, 12, 29, 0, 0)

cur_week = last_week + timedelta(weeks=1)
# Do some work with date
# set last week variable to cur week and repeat
last_week = cur_week

source_dt = event_dt - timedelta(weeks=4)
# Use source datetime to look up market factors

अभ्यास करते हैं!

इंटरमीडिएट Python फॉर फाइनेंस