Detailed explanation of python time processing

1. Two ways to get the current time:

import datetime, time

now = time.strftime("%Y-%m-%d %H:%M:%S")

print now

now = datetime.datetime.now()

print now

2. Get the date of the last day of last month (the first day of this month minus 1 day)

last = datetime.date (datetime.date.today().year,datetime.date.today().month,1)-datetime.timedelta(1)

print last

3. Get the time difference (the time difference unit is seconds, often used in calculation programs running time)

starttime = datetime.datetime.now()

#long running

endtime = datetime.datetime.now()

print (endtime - starttime).seconds

4 .Calculate the time 10 hours backward from the current time

d1 = datetime.datetime.now()

d3 = d1 + datetime.timedelta(hours=10)

d3.ctime()

The two commonly used classes are: datetime and timedelta. They can be added or subtracted from each other. Each class has some methods and attributes to view specific values. For example, datetime can view: days (day), hours (hour), day of the week (weekday()), etc.; timedelta can view: days (days), seconds Number (seconds) etc.

5. Time and date formatting symbols in python:

%y two-digit year representation (00-99)

%Y four-digit year representation (000-9999)

%m Month (01-12)

%d Day in the month (0-31)

%H Hours in 24-hour format (0-23)

%I Hours in 12-hour format (01-12)

%M Minutes (00=59)

%S Seconds (00-59)

%a Local simplified week name

%A Local complete week name

%b Local simplified month name

%B The local complete month name

%c The local corresponding date representation and time representation

%j A day in the year (001-366)

%p The local equivalent of A.M. or P.M.

%U One year The number of the week in (00-53) Sunday is the beginning of the week

%w The day of the week (0-6), Sunday is the beginning of the week

%W The number of the week in the year (00-53) Monday is the beginning of the week Start

%x Local corresponding date representation

% (freeware)http://www.CodeHighlighter.com/-->#-*-coding:utf-8-*-

import datetime, calendar

def getYesterday():

today=datetime.date .today()

oneday=datetime.timedelta(days=1)

yesterday=today-oneday

return yesterday

def getToday():

return datetime. date.today()

#Get the dates of the previous few days for the given parameter and return a list

def getDaysByNum(num):

today=datetime.date.today()

oneday=datetime.timedelta(days=1)

li= []

for i in range(0,num):

#Today minus one day, every day minus

today=today-oneday

#Convert the date into a string #result=datetostr(today)

li.append(datetostr(today))

return li

#Convert the string into datetime type

def strtodatetime(datestr,format):

return datetime.datetime.strp time(datestr,format)

#Convert time into a string, the format is 2008-08-02

def datetostr(date):

return str(date)[0:10]

#How many days are between two dates, for example : 2008-10-03 and 2008-10-01 are two days apart

def datediff(beginDate,endDate):

format="%Y-%m-%d";

bd=strtodatetime(beginDate,format )

ed=strtodatetime(endDate,format)

oneday=datetime.timedelta(days=1)

count=0

while bd!=ed:

ed=ed-oneday

  count+=1

return count

#Get all the times in two time periods and return list

def getDays(beginDate,endDate):

format="%Y-%m-%d";

bd=strtodatetime(beginDate,format)

ed=strtodatetime(endDate,format)

oneday=datetime.timedelta(days=1)

num=datediff(beginDate,endDate)+1

li=[]

for i in range(0,num):

li.append(datetostr(ed))

ed=ed-oneday return li

#Get the current year as a string

def getYear( ):

return str(datetime.date.today())[0:4]

#Get the current month as a string

def getMonth():

return str(datetime.date.today( ))[5:7]

#Get the current day as a string

def getDay():

return str(datetime.date.today())[8:10]

def getNow() :

return datetime.datetime.now()

print getToday()

print getYesterday()

print getDaysByNum(3)

print getDays(' 2008-10-01','2008- 10-05')

print '2008-10-04 00:00:00'[0:10]

print str(getYear())+getMonth()+getDay()

print getNow()