擅长:python、mysql、java
<p>你可以试试这个代码。你知道吗</p>
<pre class="lang-py prettyprint-override"><code>df['diff'] = df.groupby('Item_Type').diff(periods=-1)
df.loc[df['diff'].isnull(),'diff'] = df['diff'].shift(1)
df = df.sort_values(by = ['diff'], ascending = False)
df = df.drop(columns = 'diff')
df
</code></pre>