<p>我有一个索引号为“l1”的列表,我想根据这些索引号用NaN替换列“a”中的值</p>
<p>当前数据</p>
<pre><code>Index A
0 Reviewer: Newbie | 35-44 on Treatment for 1
1 Reviewer: 45-54 on Treatment for less than 1
2 Reviewer: Ocetech| 65-74 Male on Treatment
3 Reviewer: virleo| 55-64 Female on Treatment
4 Reviewer: Diane perrin| 65-74 on Treatment for
</code></pre>
<p>l1=[1,3,4]</p>
<p>预期产量</p>
<pre><code>Index A
0 Reviewer: Newbie | 35-44 on Treatment for 1
1 NaN
2 Reviewer: Ocetech| 65-74 Male on Treatment
3 NaN
4 NaN
</code></pre>