import datetime
import time
import pandas as pd
now = datetime.datetime.now()
#print(now)
time1 = time.time()#时间戳
localtime1 = time.localtime()#时间元组
str1 = time.mktime(localtime1)#时间元组转换成时间戳
print(localtime1,time1,str1)
#时间元组与时间字符串的转换
strf_time = time.strftime('%Y-%m-%d %H:%M:%S', localtime1)#时间元组转换成时间字符串
print('时间元组转换成时间字符串为:',strf_time)
strp_time = time.strptime(strf_time,'%Y-%m-%d %H:%M:%S')#时间字符串转换成时间元组
print('时间字符串转换成时间元组',strp_time)
dt1 = datetime.datetime(2019,1,1,2,1,1)
dt2 = datetime.datetime(2019,1,1,2,1,10)#datetime
dt_jian = dt2-dt1 #timedelta格式
dt_timetuple=dt1.timetuple()#datetime格式转换为时间元组
print(dt_timetuple)
dt_stamp = time.mktime(dt_timetuple)#时间元组转换成时间戳
print(dt_stamp)
'''
start = time.time()
time.sleep(5)
end = time.time()
time0 = end-start
print(time0,type(time0))'''
pandas中的to_datetime函数修改时间格式为datetime
df0 = [['2016-1-1','q','11','nan'],['2016-1-2','w','33','nan'],['2016-1-3','wsq','22','nan']]
df = pd.DataFrame(df0,columns=['date','name','age','sex'])
print(df['date'],type(df['date']))
dt_datetime = pd.to_datetime(df['date'])
print('转换为datetime后:',dt_datetime,type(dt_datetime))#时间格式是datetime