<p>假设我有一个数据帧:</p>
<pre><code>Id Book
1 Harry Potter (1997)
2 Of Mice and Men (1937)
3 Babe Ruth Story, The (1948) Drama 948) Babe Ruth Story
</code></pre>
<p>如何从列中提取年份</p>
<p>输出应为:</p>
<pre><code>Id Book Title Year
1 Harry Potter 1997
2 Of Mice and Men 1937
3 Babe Ruth Story, The 1948
</code></pre>
<p>到目前为止,我已经尝试:</p>
<pre><code>movies['year'] = movies['title'].str.extract('([0-9(0-9)]+)', expand=False).str.strip()
</code></pre>
<p>及</p>
<pre><code>books['year'] = books['title'].str[-5:-1]
</code></pre>
<p>我把其他事情搞砸了,还没把它用上。有什么建议吗</p>