擅长:python、mysql、java
<p>更改数据帧的结构,使其易于操作,而不是像dict这样不易操作的格式</p>
<pre><code>df = df.set_index(['Id', 'Subject']).unstack()
Number_of_Tests
Subject History Maths Science
Id
101 10 6 8
102 5 4 7
</code></pre>
<p>现在只需根据所需条件添加一列</p>
<pre><code>df['Grade'] = np.where((df['Number_of_Tests'] > 5).all(axis=1), 'A', 'B')
</code></pre>
<p>输出</p>
<pre><code> Number_of_Tests Grade
Subject History Maths Science
Id
101 10 6 8 A
102 5 4 7 B
</code></pre>
<h3>或</h3>
<p>如果您想要<code>dict</code>无论如何</p>
<pre><code>df['Tests'] = df.groupby('Id').apply(lambda x: dict(zip(x.Subject, x.Number_of_Tests)))
</code></pre>