在Python创建日期范围列表

给定一个日期，任务是编写一个Python程序来创建一个日期范围列表，其中包含从当前日期开始的下 K 个日期。

例子：

Input : test_date = datetime.datetime(1997, 1, 4), K = 5

Output : [datetime.datetime(1997, 1, 4, 0, 0), datetime.datetime(1997, 1, 5, 0, 0), datetime.datetime(1997, 1, 6, 0, 0), datetime.datetime(1997, 1, 7, 0, 0), datetime.datetime(1997, 1, 8, 0, 0)]

Explanation : 5 dates after 4 January are extracted in list.

Input : test_date = datetime.datetime(1997, 1, 4), K = 4

Output : [datetime.datetime(1997, 1, 4, 0, 0), datetime.datetime(1997, 1, 5, 0, 0), datetime.datetime(1997, 1, 6, 0, 0), datetime.datetime(1997, 1, 7, 0, 0)]

Explanation : 4 dates after 4 January are extracted in list.

方法 #1：使用timedelta() +列表理解

在这种情况下，我们可以使用 timedelta() 将连续的增量添加到 day，并且使用列表理解来迭代所需的大小并构建所需的结果。

Python3

# Python3 code to demonstrate working of
# Get Construct Next K dates List
# Using timedelta() + list comphehension
import datetime
  
# initializing date
test_date = datetime.datetime(1997, 1, 4)
               
# printing original date
print("The original date is : " + str(test_date))
  
# initializing K 
K = 5
  
# timedelta() gets successive dates with 
# appropriate difference
res = [test_date + datetime.timedelta(days=idx) for idx in range(K)]
  
# printing result
print("Next K dates list : " + str(res))

输出：

The original date is : 1997-01-04 00:00:00

Next K dates list : [datetime.datetime(1997, 1, 4, 0, 0), datetime.datetime(1997, 1, 5, 0, 0), 

datetime.datetime(1997, 1, 6, 0, 0), datetime.datetime(1997, 1, 7, 0, 0), datetime.datetime(1997, 1, 8, 0, 0)]

方法 #2：使用count() +生成器函数

在此，我们执行与上述函数类似的任务，使用生成器执行日期连续任务。

蟒蛇3

# Python3 code to demonstrate working of
# Get Construct Next K dates List
# Using count() + generator function
import datetime
import itertools
  
# initializing date
test_date = datetime.datetime(1997, 1, 4)
               
# printing original date
print("The original date is : " + str(test_date))
  
# initializing K 
K = 5
  
# timedelta() gets successive dates with 
# appropriate difference
gen_fnc = (
  test_date - datetime.timedelta(days=idx) for idx in itertools.count())
  
# islice passes counter
res = itertools.islice(gen_fnc, K)
  
# printing result
print("Next K dates list : " + str(list(res)))

输出：

The original date is : 1997-01-04 00:00:00

Next K dates list : [datetime.datetime(1997, 1, 4, 0, 0), datetime.datetime(1997, 1, 3, 0, 0), 

datetime.datetime(1997, 1, 2, 0, 0), datetime.datetime(1997, 1, 1, 0, 0), datetime.datetime(1996, 12, 31, 0, 0)]