决策分类树
引入
from sklearn.tree import DecisionTreeClassifier
DecisionTreeClassifier(criterion='gini',splitter='best',max_depth=None, \
min_samples_split=2,min_samples_leaf=1, \
min_weight_fraction_leaf=0.0,max_features=None, \
random_state=None,max_leaf_nodes=None, \
min_impurity_dec