擅长:python、mysql、java
<pre><code>julian = df.DATA_BLOCK_CODE_1.str[4:].str.extract("([1-9][0-9]?[0-9]?)")
df["DATA_BLOCK_CODE_1"] = df.DATA_BLOCK_CODE_1.str[:4] + "-" + julian
df['DATA_BLOCK_CODE_1'] = pd.to_datetime(df['DATA_BLOCK_CODE_1'], format='%Y-%j')
</code></pre>
<p><a href="https://i.stack.imgur.com/IuK2g.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/IuK2g.png" alt="enter image description here"/></a></p>
<p>正则表达式要求数字以除0以外的任何数字开头。(我假设<code>DATA_BLOCK_CODE_1</code>是字符串类型。)</p>