擅长:python、mysql、java
<p>您可以使用<code>iloc</code>访问器对列进行操作:</p>
<pre><code># convert month to days
n_days = 25 * 30
# both will return a boolean series
t1 = df.iloc[:,0].apply(lambda x: (x - pd.to_datetime('today')).days).gt(n_days)
t2 = df.iloc[0].isna()
# remove unwanted dates
df1 = df.loc[t1 & t2]
</code></pre>
<blockquote>
<p><strong>Sample Data</strong></p>
</blockquote>
<pre><code>period = pd.date_range(start='20130101', freq='M', periods=1000)
df = pd.DataFrame({'period': period})
</code></pre>