更改xgb.plot_tree（）中的字体大小

Question

如何更改xgb.plot_tree()图中的字体大小？

我作图如下：

import xgboost as xgb
import matplotlib.pylab as plt
%matplotlib inline
from matplotlib.pylab import rcParams

# ...omitting code for training the xgboost model...

xgb.plot_tree(clf, num_trees=2)

并且我尝试增加字体大小：

font = {'size'   : 22}
plt.rc('font', **font)

或带有：

plt.rcParams.update({'font.size': 32})

但是字体大小是相同的。如何在xgb.plot_tree()中更改字体大小？

Answer 1

希望这会有所帮助，我认为您应该首先设置matplotlib参数。

Answer 2

def plot_tree(xgb_model, filename, rankdir='UT'):
    """
    Plot the tree in high resolution
    :param xgb_model: xgboost trained model
    :param filename: the pdf file where this is saved
    :param rankdir: direction of the tree: default Top-Down (UT), accepts:'LR' for left-to-right tree
    :return:
    """
    import xgboost as xgb
    import os
    gvz = xgb.to_graphviz(xgb_model, num_trees=xgb_model.best_iteration, rankdir=rankdir)
    _, file_extension = os.path.splitext(filename)
    format = file_extension.strip('.').lower()
    data = gvz.pipe(format=format)
    full_filename = filename
    with open(full_filename, 'wb') as f:
        f.write(data)

您可以尝试以下电话。我更喜欢'pdf'版本，因为它提供了可以放大到无穷大的矢量图像。

plot_tree(xgb_model, 'xgboost_test_tree.pdf')
plot_tree(xgb_model, 'xgboost_test_tree.png')
plot_tree(xgb_model, 'xgboost_test_tree_LR.pdf', 'LR')
plot_tree(xgb_model, 'xgboost_test_tree_LR.png', 'LR')