def draw_tree(tree, path):
dot_data = StringIO()
dot_data.seek(0) # to reset graph?
dot_data.truncate(0) # to reset graph?
export_graphviz(tree,
out_file=dot_data,
feature_names=tree.feature_names,
filled=True,
impurity=False,
proportion=True,
rounded=True,
special_characters=True,
node_ids=True)
graph = pydotplus.graph_from_dot_data(dot_data.getvalue())
open(path, 'wb').write(Image(graph.create_png()).data)
test_prediction_rate = get_correct_ratio(test_results, test_survived)
print('{} : {}'.format("test_prediction_rate", test_prediction_rate))
dot_data = StringIO()
export_graphviz(titanic_tree,
out_file=dot_data,
filled=True,
rounded=True,
special_characters=True,
feature_names=titanic_data_features.columns.values,
class_names=["Died", "Survived"])
graph = pydotplus.graph_from_dot_data(dot_data.getvalue())
graph.write_png('tree.png')
png_str = graph.create_png(prog='dot')
# treat the dot output string as an image file
sio = StringIO()
sio.write(png_str)
sio.seek(0)
img = mpimg.imread(sio)
# plot the image
imgplot = plt.imshow(img, aspect='equal')
plt.show(block=False)
