我想创建一个日期列表,从今天开始,追溯到任意天数,例如,在我的示例中是100天。还有比这更好的办法吗?
import datetime
a = datetime.datetime.today()
numdays = 100
dateList = []
for x in range (0, numdays):
dateList.append(a - datetime.timedelta(days = x))
print dateList
我想创建一个日期列表,从今天开始,追溯到任意天数,例如,在我的示例中是100天。还有比这更好的办法吗?
import datetime
a = datetime.datetime.today()
numdays = 100
dateList = []
for x in range (0, numdays):
dateList.append(a - datetime.timedelta(days = x))
print dateList
当前回答
from datetime import datetime, timedelta
from dateutil import parser
def getDateRange(begin, end):
""" """
beginDate = parser.parse(begin)
endDate = parser.parse(end)
delta = endDate-beginDate
numdays = delta.days + 1
dayList = [datetime.strftime(beginDate + timedelta(days=x), '%Y%m%d') for x in range(0, numdays)]
return dayList
其他回答
从这个问题的标题中,我希望找到类似range()的东西,这将让我指定两个日期并创建一个包含所有日期的列表。这样,如果事先不知道,就不需要计算这两个日期之间的天数。
所以,冒着有点跑题的风险,这句话就可以了:
import datetime
start_date = datetime.date(2011, 1, 1)
end_date = datetime.date(2014, 1, 1)
dates_2011_2013 = [ start_date + datetime.timedelta(n) for n in range(int ((end_date - start_date).days))]
所有功劳都归于这个答案!
你可以写一个生成器函数,返回从今天开始的日期对象:
import datetime
def date_generator():
from_date = datetime.datetime.today()
while True:
yield from_date
from_date = from_date - datetime.timedelta(days=1)
这个生成器返回从今天开始的日期,一次返回一天。以下是前3次约会的方法:
>>> import itertools
>>> dates = itertools.islice(date_generator(), 3)
>>> list(dates)
[datetime.datetime(2009, 6, 14, 19, 12, 21, 703890), datetime.datetime(2009, 6, 13, 19, 12, 21, 703890), datetime.datetime(2009, 6, 12, 19, 12, 21, 703890)]
与循环或列表推导相比,这种方法的优点是可以返回任意多次。
Edit
使用生成器表达式代替函数的更紧凑的版本:
date_generator = (datetime.datetime.today() - datetime.timedelta(days=i) for i in itertools.count())
用法:
>>> dates = itertools.islice(date_generator, 3)
>>> list(dates)
[datetime.datetime(2009, 6, 15, 1, 32, 37, 286765), datetime.datetime(2009, 6, 14, 1, 32, 37, 286836), datetime.datetime(2009, 6, 13, 1, 32, 37, 286859)]
我知道这个回答有点晚,但我也遇到了同样的问题,我认为Python的内部范围函数在这方面有点缺乏,所以我在我的util模块中重写了它。
from __builtin__ import range as _range
from datetime import datetime, timedelta
def range(*args):
if len(args) != 3:
return _range(*args)
start, stop, step = args
if start < stop:
cmp = lambda a, b: a < b
inc = lambda a: a + step
else:
cmp = lambda a, b: a > b
inc = lambda a: a - step
output = [start]
while cmp(start, stop):
start = inc(start)
output.append(start)
return output
print range(datetime(2011, 5, 1), datetime(2011, 10, 1), timedelta(days=30))
你也可以使用日期序数来简化:
def date_range(start_date, end_date):
for ordinal in range(start_date.toordinal(), end_date.toordinal()):
yield datetime.date.fromordinal(ordinal)
或者像评论中建议的那样,你可以创建一个这样的列表:
date_range = [
datetime.date.fromordinal(ordinal)
for ordinal in range(
start_date.toordinal(),
end_date.toordinal(),
)
]
我想用一个简单(不完整)的日期范围实现来发表我的意见:
from datetime import date, timedelta, datetime
class DateRange:
def __init__(self, start, end, step=timedelta(1)):
self.start = start
self.end = end
self.step = step
def __iter__(self):
start = self.start
step = self.step
end = self.end
n = int((end - start) / step)
d = start
for _ in range(n):
yield d
d += step
def __contains__(self, value):
return (
(self.start <= value < self.end) and
((value - self.start) % self.step == timedelta(0))
)