Python日期和时间

datetime:
日期：datetime.date.today()
日期和时间：datetime.datetime.now()
1000天之后：datetime.datetimedelta(days=1000)
打印格式的问题：isoformat(),strftime()
字符串转换：strptime()

time:
datetime.time(12,11,30)
time.time()   实际时间
time.clock() CPU时间
time.sleep() 休眠

>>> import datetime

>>> a=datetime.date.today()
>>> a
datetime.date(2015, 10, 20)
>>> a.day
20
>>> a.year
2015
>>> a.month
10

>>> b=datetime.datetime.now()
>>> b
datetime.datetime(2015, 10, 20, 15, 54, 34, 345931)

>>> a=datetime.date.today()
>>> d=datetime.timedelta(days=1000)
>>> (a+d).isoformat()
‘2018-07-16‘

>>> (a+d).strftime(‘%m/%d/%Y‘)
‘07/16/2018‘

>>> e=datetime.timedelta(hours=1000)
>>> b=datetime.datetime.now()
>>> (e+b).isoformat()
‘2015-12-01T08:15:20.952474‘

>>> sad_day=datetime.datetime.strptime(‘2014-09-15‘,‘%Y-%m-%d‘)
>>> b=datetime.datetime.now()
>>> print b-sad_day
400 days, 16:23:09.111938

>>> sad_day>b
False

>>> print datetime.time(12,11,30)
12:11:30

import time

a=input("please input 0 or 1:")

start_time = time.time()
start_clock = time.clock()


if a:
    sum_i=0
    for i in range(100000):
        sum_i+=i
else:
    sum_i=sum(range(100000))

print sum_i

time.sleep(2)
end_time = time.time()
end_clock = time.clock()

print "time-delta:"
print start_time-end_time
print "clock-delta:"
print start_clock-end_clock

[root@lxd python]# python date.py 
please input 0 or 1:0
4999950000
time-delta:
-2.0064599514
clock-delta:
-0.01
[root@lxd python]# python date.py 
please input 0 or 1:1
4999950000
time-delta:
-2.02046704292
clock-delta:
-0.01