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<p>我试图从一个数据帧创建一个摘要表，如下例所示。列具有一组唯一值的列表。你知道吗</p>
<pre class="lang-py prettyprint-override"><code>tdf = pd.DataFrame({"A": ["ind1", "ind2", "ind1", "ind3", "ind3", "ind1", "ind1"],
"B": ["ind3", "ind1", "ind3", "ind1", "ind1","ind3", "ind2"],
"C": ["ind1","ind1","ind2","ind2","ind3","ind3","ind3"],
"D": ["ind3","ind1","ind2","ind3","ind2","ind1","ind3"],
"E": ["ind1","ind3","ind1","ind1","ind2","ind2","ind2"]})
</code></pre>
<p>然后，我需要创建一个新的类似于表的对象，该对象有一个与列相对应的头，以及3个具有设置索引值的频率计数的行。你知道吗</p>
<pre class="lang-py prettyprint-override"><code>setvalues = ['ind1','ind2','ind3']
result = pd.DataFrame({"A": [4,1,2],
"B": [3,1,3],
"C": [2,2,3],
"D": [2,2,3],
"E": [3,3,1]})
</code></pre>
<p>我尝试了透视表，但它没有返回所需的格式。在Excel中，我可以设置索引值并对列进行简单的COUNTIF，但是我很难用Python实现它。你知道吗</p>
