擅长:python、mysql、java
<p>似乎需要为<a href="http://pandas.pydata.org/pandas-docs/stable/indexing.html#boolean-indexing" rel="nofollow">^{<cd1>}</a>添加第二个条件:</p>
<pre><code>import pandas as pd
f = pd.read_csv('chart.csv')
f_set = f[(f.year >= 2002) & (f.year < 2010)]
print (f_set.groupby('y').namefromchart.nunique())
</code></pre>
<p>另一个带有<a href="http://pandas.pydata.org/pandas-docs/stable/generated/pandas.Series.between.html" rel="nofollow">^{<cd2>}</a>的解决方案默认为<em>包含</em>:</p>
<pre><code>f_set = f[f.year.between(2002,2009)]
</code></pre>