Date/Time Objects
Creating and Manipulating Date/Time Objects in Python
1. Creating Date and Time Objects
Creating Date Objects
python
from datetime import date, time, datetime
# Create date objects
date1 = date(2023, 12, 25) # Christmas 2023
date2 = date(2024, 1, 1) # New Year 2024
date3 = date(2023, 6, 15) # Random date
print("Date Objects:")
print(f"Christmas: {date1}")
print(f"New Year: {date2}")
print(f"Random date: {date3}")
Creating Time Objects
python
# Create time objects
time1 = time(14, 30, 45) # 2:30:45 PM
time2 = time(9, 0, 0) # 9:00:00 AM
time3 = time(23, 45, 30, 500000) # 11:45:30.500000 PM
print("\nTime Objects:")
print(f"Time 1: {time1}")
print(f"Time 2: {time2}")
print(f"Time 3: {time3}")
Creating DateTime Objects
python
# Create datetime objects
dt1 = datetime(2023, 12, 25, 14, 30, 45) # Christmas afternoon
dt2 = datetime(2024, 1, 1, 0, 0, 0) # New Year midnight
dt3 = datetime(2023, 6, 15, 9, 15, 30) # Random datetime
print("\nDateTime Objects:")
print(f"Christmas: {dt1}")
print(f"New Year: {dt2}")
print(f"Random: {dt3}")
2. Using combine() Method
Combine Date and Time
python
from datetime import date, time, datetime
# Create separate date and time
my_date = date(2023, 12, 25)
my_time = time(18, 30, 0) # 6:30 PM
# Combine them into datetime
combined_dt = datetime.combine(my_date, my_time)
print(f"Combined DateTime: {combined_dt}")
# Output: 2023-12-25 18:30:00
# Multiple combinations
dates = [date(2023, 12, 25), date(2024, 1, 1), date(2024, 2, 14)]
times = [time(9, 0, 0), time(14, 30, 0), time(19, 0, 0)]
for d, t in zip(dates, times):
combined = datetime.combine(d, t)
print(f"{d} at {t} -> {combined}")
3. Comparing Objects
Date Comparisons
python
from datetime import date
# Create dates
today = date(2023, 12, 25)
tomorrow = date(2023, 12, 26)
yesterday = date(2023, 12, 24)
print("Date Comparisons:")
print(f"today > yesterday: {today > yesterday}") # True
print(f"today < tomorrow: {today < tomorrow}") # True
print(f"today == yesterday: {today == yesterday}") # False
# Check if date is in range
start_date = date(2023, 12, 1)
end_date = date(2023, 12, 31)
print(f"Is today in December 2023? {start_date <= today <= end_date}") # True
DateTime Comparisons
python
from datetime import datetime
# Create datetimes
meeting1 = datetime(2023, 12, 25, 10, 0, 0)
meeting2 = datetime(2023, 12, 25, 14, 0, 0)
meeting3 = datetime(2023, 12, 26, 10, 0, 0)
print("\nDateTime Comparisons:")
print(f"Meeting1 before Meeting2: {meeting1 < meeting2}") # True
print(f"Meeting2 after Meeting3: {meeting2 > meeting3}") # False
print(f"Same day different times: {meeting1.date() == meeting2.date()}") # True
4. Adding and Subtracting Objects
Using timedelta for Arithmetic
python
from datetime import datetime, timedelta
current_dt = datetime(2023, 12, 25, 10, 0, 0)
print(f"Current: {current_dt}")
# Adding time
one_day_later = current_dt + timedelta(days=1)
three_hours_later = current_dt + timedelta(hours=3)
one_week_later = current_dt + timedelta(weeks=1)
print(f"One day later: {one_day_later}")
print(f"Three hours later: {three_hours_later}")
print(f"One week later: {one_week_later}")
# Subtracting time
one_day_ago = current_dt - timedelta(days=1)
two_hours_ago = current_dt - timedelta(hours=2)
print(f"One day ago: {one_day_ago}")
print(f"Two hours ago: {two_hours_ago}")
Complex Date Arithmetic
python
from datetime import datetime, timedelta
# Project timeline example
project_start = datetime(2023, 12, 25, 9, 0, 0)
# Add various time periods
design_end = project_start + timedelta(days=7) # 1 week for design
development_end = design_end + timedelta(days=14) # 2 weeks for development
testing_end = development_end + timedelta(days=7) # 1 week for testing
print("Project Timeline:")
print(f"Start: {project_start}")
print(f"Design complete: {design_end}")
print(f"Development complete: {development_end}")
print(f"Testing complete: {testing_end}")
# Calculate total project duration
total_duration = testing_end - project_start
print(f"Total project duration: {total_duration.days} days")
5. Complete Example Programs
Program 1: Event Scheduler
python
from datetime import datetime, timedelta, date, time
class EventScheduler:
def __init__(self):
self.events = []
def add_event(self, name, event_date, event_time, duration_hours=1):
event_dt = datetime.combine(event_date, event_time)
end_time = event_dt + timedelta(hours=duration_hours)
self.events.append({
'name': name,
'start': event_dt,
'end': end_time
})
print(f"Event '{name}' scheduled from {event_dt} to {end_time}")
def list_events(self):
print("\nScheduled Events:")
for event in sorted(self.events, key=lambda x: x['start']):
duration = event['end'] - event['start']
print(f"- {event['name']}: {event['start']} to {event['end']} ({duration})")
# Usage
scheduler = EventScheduler()
# Schedule events
scheduler.add_event("Team Meeting", date(2023, 12, 26), time(10, 0, 0), 2)
scheduler.add_event("Lunch", date(2023, 12, 26), time(12, 30, 0), 1)
scheduler.add_event("Client Call", date(2023, 12, 27), time(14, 0, 0), 1.5)
scheduler.list_events()
Program 2: Date Calculator
python
from datetime import date, timedelta
class DateCalculator:
@staticmethod
def calculate_age(birth_date):
today = date.today()
age = today.year - birth_date.year
# Check if birthday hasn't occurred this year yet
if today.month < birth_date.month or (today.month == birth_date.month and today.day < birth_date.day):
age -= 1
return age
@staticmethod
def days_until(target_date):
today = date.today()
return (target_date - today).days
@staticmethod
def add_business_days(start_date, business_days):
current_date = start_date
added_days = 0
while added_days < business_days:
current_date += timedelta(days=1)
# Skip weekends (0=Monday, 6=Sunday)
if current_date.weekday() < 5:
added_days += 1
return current_date
# Usage
calculator = DateCalculator()
# Calculate age
birthday = date(1990, 6, 15)
age = calculator.calculate_age(birthday)
print(f"Age: {age} years")
# Days until New Year
new_year = date(2024, 1, 1)
days_left = calculator.days_until(new_year)
print(f"Days until New Year: {days_left}")
# Add business days
start = date(2023, 12, 25) # Monday
deadline = calculator.add_business_days(start, 5) # Add 5 business days
print(f"Start: {start}, Deadline: {deadline}")
Program 3: Time Difference Calculator
python
from datetime import datetime
class TimeDifferenceCalculator:
@staticmethod
def time_between(dt1, dt2):
difference = abs(dt2 - dt1)
days = difference.days
seconds = difference.seconds
hours = seconds // 3600
minutes = (seconds % 3600) // 60
seconds = seconds % 60
return {
'total_seconds': difference.total_seconds(),
'days': days,
'hours': hours,
'minutes': minutes,
'seconds': seconds
}
@staticmethod
def format_difference(dt1, dt2):
diff = TimeDifferenceCalculator.time_between(dt1, dt2)
if dt1 < dt2:
direction = "after"
else:
direction = "before"
parts = []
if diff['days'] > 0:
parts.append(f"{diff['days']} days")
if diff['hours'] > 0:
parts.append(f"{diff['hours']} hours")
if diff['minutes'] > 0:
parts.append(f"{diff['minutes']} minutes")
if diff['seconds'] > 0:
parts.append(f"{diff['seconds']} seconds")
time_str = ", ".join(parts)
return f"{dt2} is {time_str} {direction} {dt1}"
# Usage
calculator = TimeDifferenceCalculator()
# Calculate differences
start_time = datetime(2023, 12, 25, 10, 0, 0)
end_time = datetime(2023, 12, 26, 14, 30, 45)
difference = calculator.time_between(start_time, end_time)
print("Time Difference:")
for unit, value in difference.items():
print(f"{unit}: {value}")
formatted = calculator.format_difference(start_time, end_time)
print(f"\nFormatted: {formatted}")
Key Points to Remember:
- Creating Objects:
date(year, month, day)time(hour, minute, second)datetime(year, month, day, hour, minute, second)
- Combining: Use
datetime.combine(date, time) - Comparing: Use standard operators (
<,>,==, etc.) - Arithmetic: Use
timedeltafor adding/subtracting time - Always import:
from datetime import date, time, datetime, timedelta
These examples show how powerful and flexible Python’s datetime module is for handling all kinds of date and time operations!
