Iterating through a range of dates in Python

The range of dates is defined by the starting date, ending date, and all dates in between. In Python, we have some built−in functions such as datetime.date(), range(), timedelta(), and, delta() will be used to iterate through a range of dates.

Let’s take an example of this.

The Starting Date, 26−06−2023

The Ending Date, 30−06−2023

Therefore, the final result of a range of dates becomes:

26−06−2023

27−06−2023

28−06−2023

29−06−2023

30−06−2023

Syntax

The following syntax is used in the examples-

datetime.date()

The date is an instance function of the datetime library of Python that returns date objects.

range()

The built−in function range() is defined by returning the order of numbers according to the given length.

timedelta()

The timedelta() is an in−built Python function that follows the library named datetime and returns the differences of dates.

Using while loop

In the following example, start importing the module datetime that will be used to set the dates. Next, initialize the two different dates in the respective variable that will be used to calculate the differences. Then using the while loop it set the condition based on <= operator to get the ranges of dates. Using the built−in function timedelta() with += operator it shows all the dates.

Example

import datetime
start = datetime.date(2023, 6, 3)
end = datetime.date(2023, 6, 4)
res_date = start
print("The range dates are:")
while res_date <= end:
    print(res_date)
    res_date += datetime.timedelta(days=1)

Output

 The range dates are: 
 2023-06-03 
 2023-06-04

Using List Comprehension

In the following example, begin the program with a datetime module that contains the information of dates. Then using list comprehension it finds the differences between two dates. This can be done by using timedelta function with an increasing number of days to start the date until the end date is reached.

Example

import datetime
start = datetime.date(2023, 6, 16)
end = datetime.date(2023, 6, 19)
date_of_range = [start + datetime.timedelta(days=delta) for delta in range((end - start).days + 1)]
print("The range dates are:")
for res_date in date_of_range:
    print(res_date)

Output

The range dates are: 
2023-06-16 
2023-06-17 
2023-06-18
2023-06-19 

Using timedelta()

In the following example, we will use the for loop where variable delta iterates through both the initialization dates using a built−in function range(). Next, add the start date with timedelta() where it accepts the parameters− days=delta that returns the differences between two dates and generates the final result of the program.

Example

import datetime
start = datetime.date(2023, 6, 1)
end = datetime.date(2023, 6, 5)
print("The range of dates:")
# Calculate the differences using range()
for delta in range((end - start).days + 1):
    result_date = start + datetime.timedelta(days=delta)
    print(result_date)

Output

The range of dates: 
2023-06-01 
2023-06-02 
2023-06-03 
2023-06-04 
2023-06-05

Using Recursive function to generate the even dates in the range list

In the following example, the program uses datetime library that will be used to set the dates. Then using the recursive function it accepts two parameters to set the start and end date which will be used to work on a range of dates. Next, using while loop it set the difference condition based on <= operator and calculates the even date by using timedelta(). Moving ahead to initialize the start and end dates in the respective variable. Finally, using the for loop it iterates both the variables i.e. start_date and end_date to generate the even dates.

Example

import datetime
# Function definition
def range_date(start, end):
    res_date = start
    while res_date <= end:
        yield res_date
        res_date += datetime.timedelta(days=2)
start_date = datetime.date(2023, 6, 10)
end_date = datetime.date(2023, 6, 20)
print("The range dates are-")
for c_date in range_date(start_date, end_date):
    print(c_date)

Output

The range dates are-
2023-06-10
2023-06-12
2023-06-14
2023-06-16
2023-06-18
2023-06-20

Conclusion

The iteration of range of dates specifies the two variables i.e. start and end date. Using for loop it iterates the dates based on specific conditions and operations. Then use the timedelta() function to return all the dates between two variables. This type of program helps to build the mathematical formula based on searching.