擅长:python、mysql、java
<p>每<a href="http://pandas.pydata.org/pandas-docs/version/0.17.0/generated/pandas.DataFrame.filter.html" rel="noreferrer">the docs</a></p>
<blockquote>
<p>Arguments are mutually exclusive, but this is not checked for</p>
</blockquote>
<p>看来,第一个可选参数<code>items=[0]</code>胜过第三个可选参数<code>regex=r'(Hel|Just)'</code>。</p>
<pre><code>In [194]: df.filter([0], regex=r'(Hel|Just)', axis=0)
Out[194]:
0 1
0 Hello World
</code></pre>
<p>相当于</p>
<pre><code>In [201]: df.filter([0], axis=0)
Out[201]:
0 1
0 Hello World
</code></pre>
<p>它只是选择索引值在<code>[0]</code>中沿0轴的行。</p>
<hr/>
<p>为了得到想要的结果,可以使用<code>str.contains</code>创建一个布尔掩码,
并使用<code>df.loc</code>选择行:</p>
<pre><code>In [210]: df.loc[df.iloc[:,0].str.contains(r'(Hel|Just)')]
Out[210]:
0 1
0 Hello World
1 Just Wanted
</code></pre>