Sklearn plot_tree plot is too small

I think the setting you are looking for is fontsize. You have to balance it with max_depth and figsize to get a readable plot. Here is an example

from sklearn import treefrom sklearn.datasets import load_irisimport matplotlib.pyplot as plt# load dataX, y = load_iris(return_X_y=True)# create and train modelclf = tree.DecisionTreeClassifier(max_depth=4)  # set hyperparameterclf.fit(X, y)# plot treeplt.figure(figsize=(12,12))  # set plot size (denoted in inches)tree.plot_tree(clf, fontsize=10)plt.show()

If you want to capture structure of the whole tree I guess saving the plot with small font and high dpi is the solution. Then you can open a picture and zoom to the specific nodes to inspect them.

# create and train modelclf = tree.DecisionTreeClassifier()clf.fit(X, y)# save plotplt.figure(figsize=(12,12))tree.plot_tree(clf, fontsize=6)plt.savefig('tree_high_dpi', dpi=100)

Here is an example of how it looks like on the bigger tree.

What about setting the size of the image before hand:

clf = tree.DecisionTreeClassifier()clf = clf.fit(X, y)fig, ax = plt.subplots(figsize=(10, 10))  # whatever size you wanttree.plot_tree(clf.fit(X, y), ax=ax)plt.show()