擅长:python、mysql、java
<p>简单的<code>sum()</code>怎么样:</p>
<pre class="lang-py prettyprint-override"><code>res=df.groupby(["location_id"], as_index=False).agg({"city": "last", "all_poi": "sum"})
res["all_poi"]=res["all_poi"].map(set)
</code></pre>
<p>产出:</p>
<pre class="lang-py prettyprint-override"><code>Before
location_id ... all_poi
0 6265981 ... [Mount St. Louis Moonstone, Horseshoe Valley, Lake Muskoka]
1 6265981 ... [Mount St. Louis Moonstone, Little Lake Park, Bamboo Spa, Lake Huron]
After:
location_id ... all_poi
0 6265981 ... {Horseshoe Valley, Lake Muskoka, Lake Huron, Bamboo Spa, Little Lake Park, Mount St. Louis Moonstone}
</code></pre>