将列表中的第一个元素从字符串更改为日期 [英] Change the first element in a list from string to date

问题描述

我有以下文本文件，其中包含以下列表：

I have the following text file that has these lists :

['2009-06-12 14:19:28 ', '0']
['2009-06-13 00:58:10 ', '0']
['2009-06-13 01:00:25 ', '0']
['2009-06-15 03:24:23 ', '0']
['2009-06-25 17:50:46 ', '0']
['2009-06-29 20:54:52 ', '0']
['2009-06-30 20:31:19 ', '0']
['2009-07-09 03:01:25 ', '0']
['2009-07-12 14:45:53 ', '0']
['2009-07-12 15:09:38 ', '0']

第二个元素是整数，但是，第一个元素是一个字符串。我需要每个lis的第一个元素是一个日期而不是字符串？



我试过这段代码：

The second element is an integer, however, the first element is a string. I need the first element of each lis to be a date instead of string?

I tried this code:

word[0]=datetime.strptime(word[0],'%Y/%m/%d %H:%M:%S')

但我收到此错误：

but I get this error:

ValueError: time data '2009-04-02 22:50:06 ' does not match format '%Y/%m/%d %H:%M:%S'

我清理数据的当前代码如下：

the current code I have that cleans the data is the following:

with open('newdata.txt') as f:
    for line in f:
       tweet=re.sub(r'T\t',"",line)
       t=re.sub(r'W\t',"\/\/",tweet)
       data=t.split("\/\/")
       sentiment_value= s.sentiment(data[1])
       data.append(sentiment_value)

       words = [w.replace('pos', '1') for w in data]
       word=[w.replace('neg','0')for w in words]
       del word[1]
       print(word)

我的尝试：



我试过这段代码：

What I have tried:

I tried this code:

word[0]=datetime.strptime(word[0].strip(),'%Y/%m/%d %H:%M:%S')

但是我收到了这个错误：

but I get this error:

ValueError: time data '2009-04-02 22:50:06 ' does not match format '%Y/%m/%d %H:%M:%S'

推荐答案

初看......似乎你需要更换：

On the first look... Seems you need to replace:

dt = datetime.strptime("2009-04-02 22:50:06",'%Y/%m/%d %H:%M:%S')

with：

with:

dt = datetime.strptime("2009-04-02 22:50:06", "%Y-%m-%d %H:%M:%S")

见：

将字符串转换为日期时间 [ ^ ]

8.1。 datetime - 基本日期和时间类型 - Python 3.6.6rc1文档 [ ^ ]



但是...... 文档 [ ^ ]也声明：

See:
Converting Strings To Datetime[^]
8.1. datetime — Basic date and time types — Python 3.6.6rc1 documentation[^]

But... the documentation[^] states also:

Quote：

使用不完整或含糊不清的ISO 8601指令调用strptime（）将引发 ValueError 。



（.. 。）



因为格式取决于当前的语言环境，所以在对输出值进行假设时应该小心。字段排序会有所不同（例如，月/日/年与日/月/年） ，输出可能包含使用区域设置的默认编码编码的Unicode字符（例如，如果当前区域设置是ja_JP，则默认编码可以是eucJP，SJIS或utf-8中的任何一个;使用区域设置.getlocale（）确定当前语言环境的编码。

Calling strptime() with incomplete or ambiguous ISO 8601 directives will raise a ValueError.

(...)

Because the format depends on the current locale, care should be taken when making assumptions about the output value. Field orderings will vary (for example, "month/day/year" versus "day/month/year"), and the output may contain Unicode characters encoded using the locale’s default encoding (for example, if the current locale is ja_JP, the default encoding could be any one of eucJP, SJIS, or utf-8; use locale.getlocale() to determine the current locale’s encoding).

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