<p dir="auto">It cost me quite some time to figure out that if I want to have a structured representation of my underlying decision tree I can use the <code class="notranslate">tree_</code> attribute of the <a href="http://scikit-learn.org/stable/modules/generated/sklearn.tree.DecisionTreeClassifier.html#examples-using-sklearn-tree-decisiontreeclassifier" rel="nofollow">DecisionTreeClassifier</a> at the bottom of the attribute list. Further down the bottom there is also an example <a href="http://scikit-learn.org/stable/auto_examples/tree/plot_unveil_tree_structure.html#sphx-glr-auto-examples-tree-plot-unveil-tree-structure-py" rel="nofollow">'Understanding the decision tree structure'</a>.</p>
<p dir="auto">However it personally took me days to figure all of this out. Mainly because I was under the assumption that <code class="notranslate">tree_</code> is intended as a private member.</p>
<p dir="auto">It is my humble opinion that the documentation is improved significantly if it is extended with sklearn.tree.Tree API reference  together with an additional small treatise on the <a href="http://scikit-learn.org/stable/modules/tree.html" rel="nofollow">decision tree info page</a> similar as how the <code class="notranslate">export_graphviz</code> usage is discussed.</p>
<h4 dir="auto">Description</h4>
<p dir="auto">(Motivated by some questions in the mailing list)<br>
I couldn't find a place where the attributes of the underlying <code class="notranslate">tree_</code> objects of <code class="notranslate">DecisionTree&lt;Classifier/Regressor&gt;</code> were documented. They're fairly useful for getting basic information about a built tree, and many people don't know where to look in the code base to find info about them (<a href="https://github.com/scikit-learn/scikit-learn/blob/master/sklearn/tree/_tree.pyx#L490">here in _tree.pyx</a>).</p>
<p dir="auto">Is it worth linking to the file or having a page that documents all the properties?</p>