如何在python3中将str对象更改为datetime.time?
首先添加代码:如何在python3中将str对象更改为datetime.time?,python,python-3.x,datetime,Python,Python 3.x,Datetime,首先添加代码: import csv from datetime import datetime, date, time with open('T2.csv') as readcsvfile: readcsv=csv.reader(readcsvfile) header=next(readcsv) data=[] for row in readcsv: # if-else construct to read both empty & t
import csv
from datetime import datetime, date, time
with open('T2.csv') as readcsvfile:
readcsv=csv.reader(readcsvfile)
header=next(readcsv)
data=[]
for row in readcsv:
# if-else construct to read both empty & time string
if row[0]==str():
date=str()
else:date=datetime.strptime(row[0],'%y%m%d')
# stripping the 170101 part with str(ing)p(arse)time and
# changing the style/format into '%Y/%m/%d' format with strftime.
ID=str(row[5])
if row[6]==str():
O_all=str()
else:O_all=datetime.strptime(row[6],'%H:%M').strftime('%H:%M')
Combined_datetime=datetime.combine(date,O_all)
data.append([Combined_datetime,ID])
print(data)
产生以下错误:
Combined_datetime=datetime.combine(date,O_all)
TypeError: combine() argument 2 must be datetime.time, not str
但是如果我检查类型,“date”和“O_all”都是“datetime.datetime”对象。我想我错过了什么或者理解错了什么。获得名为“Combined_datetime”的时间元组的补救方法是什么?使用此代码进行更新
import csv
from datetime import datetime, date, time
with open('T2.csv') as readcsvfile:
readcsv=csv.reader(readcsvfile)
header=next(readcsv)
data=[]
Combined_datetime =
for row in readcsv:
if len(row[0])<0:
date=str()
else:
date=datetime.strptime(row[0],'%y%m%d')
ID=str(row[5])
if len(row[6])<0:
O_all=str()
else:
O_all=datetime.strptime(row[6],'%H:%M').time()
if date and O_all:
Combined_datetime = datetime.combine(date, O_all).strftime('%y%m%d %H:%M')
data.append([Combined_datetime,ID])
else:
data.append(['',ID])
print(data)
导入csv
从日期时间导入日期时间、日期、时间
将open('T2.csv')作为readcsvfile:
readcsv=csv.reader(readcsvfile)
header=next(readcsv)
数据=[]
合并日期时间=
对于readcsv中的行:
如果len(行[0])问题在别处。在读取csv时,我可以使用简单的if-else构造读取所有行(空时间被视为空字符串)。但是,当将日期和时间与datetime.combine(d,t)
组合时,它无法处理空字符串。
@amarnath您关于添加.time()
的建议很有帮助。这次我删除了空时间的行。实际上,它以这种方式重写了TypeError:combine()参数2必须是datetime.time,而不是str
error。
以下是完整的工作代码:
#Reading T2 & writing new csv
import csv
from datetime import datetime, date, time
with open('T2.csv') as readcsvfile:
readcsv=csv.reader(readcsvfile)
header=next(readcsv)
data=[]
for row in readcsv:
#if-else construct to read both empty & time string
if row[6]!=str():
d=datetime.strptime(row[0],'%y%m%d')
t=datetime.strptime(row[6],'%H:%M').time()
print(type(d))
##stripping the 170101 part with str(ing)p(arse)time and
##changing t from datetime.datetime to datetime.time with `.time()`
print(type(t))
ID=str(row[5])
Combined_datetime = datetime.combine(d, t)
data.append([Combined_datetime,ID])
print(data)
with open('T2_w3.csv','w',newline='') as writecsvfile:
writecsv=csv.writer(writecsvfile)
writecsv.writerow(['Combined_datetime','ID'])
for i in range(len(data)):
ROW=data[i]
CDT=ROW[0]
ID=ROW[1]
Final_list=[CDT,ID]
writecsv.writerow(Final_list)
由于O_all=datetime.strtime(第[6]行,'%H:%M').strftime('%H:%M').strftime('%H:%M')中的.strftime('%H:%M')
当我删除.strftime('%H:%M')
时,错误变为类型错误:combine()参数2必须是datetime.time,而不是datetime.datetime
。运气不好。错误再次是TypeError:combine()参数2必须是datetime.time,而不是str
。“O_all=time.strtime(第[6]行,'%H:%M')”也不起作用,它给出了AttributeError:type对象“datetime.time”没有属性“strtime”
我希望row[0]
,row[6]
是的,它们来自csv文件,因此默认情况下,csv.reader将一行中的每个对象读取为字符串。然后将其转换为datetime对象。一切正常,直到我尝试组合“date”和“O_all”,它们都是“datetime.datetime”对象格式。问题是,我不知道如何获取“datetime.time”而不是“datetime.datetime”对象。根据python3,第一个和第二个参数分别是date
和time
。datetime.strtime(行[6],“%H:%M”).time()
负责生成datetime.time
对象。因此,更新后的代码应该可以工作。