擅长:python、mysql、java
<p>可以构造透视表并将其与转置相乘:</p>
<pre><code>pvt = pd.pivot_table(df, index='book', columns='person', aggfunc=len, fill_value=0)
pvt.dot(pvt.T)
Out:
book dracula frankenstein rebecca
book
dracula 3 2 1
frankenstein 2 2 0
rebecca 1 0 1
</code></pre>