def choose_root():
global current_labels
global current_instances
global tree_nodes
global visual_nodes
global tree_root
global blocked_features
tree_nodes = []
feature_dict = {}
for feature in list(current_instances[0].feature_dict.keys()):
if (feature not in blocked_features):
feature_dict[feature] = calculate_global_entropy(
current_instances) - get_feature_entropy(feature)
#print(feature_dict)
feature_name = max(feature_dict, key=feature_dict.get)
node = TreeNode(parent=None,
feature_name=str(feature_name),
children_labels=None,
children_nodes=None,
is_leaf=True,
is_feature=True,
labels=get_global_labels())
root = Node(node.feature_name)
blocked_features.append(node.feature_name)
visual_nodes.append(root)
tree_nodes.append(node)
tree_root = node
node_children_labels = {}
node_children_nodes = {}
for attr in get_feature_attrs(node.feature_name):
temp_node = TreeNode(parent=node,
feature_name=None,
children_labels=None,
children_nodes=None,
is_leaf=True,
is_feature=False,
labels=get_feature_attrs(node.feature_name)[attr])
temp_visual_node = Node(str(attr) + "[" + str(temp_node.labels[0]) +
"," + str(temp_node.labels[1]) + "]",
parent=root)
node_children_labels[str(attr)] = temp_node.labels
node_children_nodes[str(attr)] = temp_node
tree_nodes.append(temp_node)
node.children_labels = node_children_labels
node.children_nodes = node_children_nodes
current_instances = []
#print(node.feature_name)
return
def check_for_pullup():
global tree_nodes
global tree_root
for key in tree_root.children_nodes.keys():
n = tree_root.children_nodes[key]
now_instances = tree_root.seen_instances
if ((n.is_feature)):
print(n.feature_name)
if (n.entropy() < n.parent.entropy()):
node = TreeNode(parent=None,
feature_name=str(n.feature_name),
children_labels=None,
children_nodes=None,
is_leaf=True,
is_feature=True,
labels=n.labels)
tree_root = node
node_children_labels = {}
node_children_nodes = {}
for attr in n.children_nodes.keys():
print(attr)
temp_node = TreeNode(parent=node,
feature_name=n.parent.feature_name,
children_labels=None,
children_nodes=None,
is_leaf=True,
is_feature=False,
labels=get_feature_attrs(
node.feature_name)[attr])
node_children_labels[str(attr)] = temp_node.labels
node_children_nodes[str(attr)] = temp_node
tree_nodes.append(temp_node)
node.children_labels = node_children_labels
node.children_nodes = node_children_nodes
create_tree(now_instances)
print("------------")
return
