def sub_tree(self, vtx_id, copy=True):
"""Return the subtree rooted on `vtx_id`.
The induced subtree of the tree has the vertices in the ancestors of vtx_id.
:Parameters:
- `vtx_id`: A vertex of the original tree.
- `copy`:
If True, return a new tree holding the subtree. If False, the subtree is
created using the original tree by deleting all vertices not in the subtree.
:returns: A sub tree of the tree. If copy=True, a new Tree is returned.
Else the subtree is created inplace by modifying the original tree.
"""
if not copy:
# remove all vertices not in the sub_tree
bunch = set(pre_order(self, vtx_id))
remove_bunch = set(self) - bunch
for vid in remove_bunch:
self._remove_vertex_properties(vid)
#self.remove_vertex(vid)
# remove parent edge
pid = self.parent(vid)
if pid is not None:
self._children[pid].remove(vid)
del self._parent[vid]
# remove children edges
for cid in self.children(vid):
self._parent[cid] = None
if vid in self._children:
del self._children[vid]
self.root = vtx_id
return self
else:
treeid_id = {}
tree = self.__class__()
tree.root = 0
for name in self.properties():
tree.add_property(name)
treeid_id[vtx_id] = tree.root
tree._add_vertex_properties(tree.root,
self.get_vertex_property(vtx_id))
subtree = pre_order(self, vtx_id)
subtree.next()
for vid in subtree:
pid = self.parent(vid)
if pid is not None:
parent = treeid_id[pid]
v = tree.add_child(parent)
treeid_id[vid] = v
tree._add_vertex_properties(v, self.get_vertex_property(vid))
return tree
def sub_tree(self, vtx_id, copy=True):
"""Return the subtree rooted on `vtx_id`.
The induced subtree of the tree has the vertices in the ancestors of vtx_id.
:Parameters:
- `vtx_id`: A vertex of the original tree.
- `copy`:
If True, return a new tree holding the subtree. If False, the subtree is
created using the original tree by deleting all vertices not in the subtree.
:returns: A sub tree of the tree. If copy=True, a new Tree is returned.
Else the subtree is created inplace by modifying the original tree.
"""
if not copy:
# remove all vertices not in the sub_tree
bunch = set(pre_order(self, vtx_id))
remove_bunch = set(self) - bunch
for vid in remove_bunch:
self._remove_vertex_properties(vid)
#self.remove_vertex(vid)
# remove parent edge
pid = self.parent(vid)
if pid is not None:
self._children[pid].remove(vid)
del self._parent[vid]
# remove children edges
for cid in self.children(vid):
self._parent[cid] = None
if vid in self._children:
del self._children[vid]
self.root = vtx_id
return self
else:
treeid_id = {}
tree = self.__class__()
tree.root = 0
for name in self.properties():
tree.add_property(name)
treeid_id[vtx_id] = tree.root
tree._add_vertex_properties(tree.root, self.get_vertex_property(vtx_id))
subtree = pre_order(self, vtx_id)
subtree.next()
for vid in subtree:
pid = self.parent(vid)
if pid is not None:
parent = treeid_id[pid]
v = tree.add_child(parent)
treeid_id[vid] = v
tree._add_vertex_properties(v, self.get_vertex_property(vid))
return tree
def add_child_tree(self, parent, tree):
"""
Add a tree after the children of the parent vertex.
Complexity has to be O(1) if tree == sub_tree()
This method copies the tree and renumbers its vertices.
Returns a map between original tree vids and the newly added vids.
:param parent: vertex identifier
:param tree: a rooted tree
:returns: dict (original tree id -> new id)
"""
treeid_id = {}
root = tree.root
root_id = self.add_child(parent)
treeid_id[root]=root_id
# pre_order traversal from root and renumbering
for vtx_id in pre_order(tree, root):
if vtx_id == root:
continue
parent = treeid_id[tree.parent(vtx_id)]
vid = self.add_child(parent)
treeid_id[vtx_id] = vid
return treeid_id
def add_child_tree(self, parent, tree):
"""
Add a tree after the children of the parent vertex.
Complexity has to be O(1) if tree == sub_tree()
This method copies the tree and renumbers its vertices.
Returns a map between original tree vids and the newly added vids.
:param parent: vertex identifier
:param tree: a rooted tree
:returns: dict (original tree id -> new id)
"""
treeid_id = {}
root = tree.root
root_id = self.add_child(parent)
treeid_id[root] = root_id
# pre_order traversal from root and renumbering
for vtx_id in pre_order(tree, root):
if vtx_id == root:
continue
parent = treeid_id[tree.parent(vtx_id)]
vid = self.add_child(parent)
treeid_id[vtx_id] = vid
return treeid_id
def sub_tree(self, vtx_id, copy=True):
"""Return the subtree rooted on `vtx_id`.
The induced subtree of the tree has the vertices in the ancestors of vtx_id.
:Parameters:
- `vtx_id`: A vertex of the original tree.
- `copy`:
If True, return a new tree holding the subtree. If False, the subtree is
created using the original tree by deleting all vertices not in the subtree.
:returns: A sub tree of the tree. If copy=True, a new Tree is returned.
Else the subtree is created inplace by modifying the original tree.
"""
if not copy:
# remove all vertices not in the sub_tree
bunch = set(pre_order(self, vtx_id))
for vid in self:
if vid not in bunch:
self.remove_vertex(vid)
self._root = vtx_id
self._parent[self._root] = None
return self
else:
treeid_id = {}
tree = Tree()
tree.root = 0
treeid_id[vtx_id] = tree.root
subtree = pre_order(self, vtx_id)
subtree.next()
for vid in subtree:
parent = treeid_id[self.parent(vid)]
v = tree.add_child(parent)
treeid_id[vid] = v
return tree
def sub_tree(self, vtx_id, copy=True):
"""Return the subtree rooted on `vtx_id`.
The induced subtree of the tree has the vertices in the ancestors of vtx_id.
:Parameters:
- `vtx_id`: A vertex of the original tree.
- `copy`:
If True, return a new tree holding the subtree. If False, the subtree is
created using the original tree by deleting all vertices not in the subtree.
:returns: A sub tree of the tree. If copy=True, a new Tree is returned.
Else the subtree is created inplace by modifying the original tree.
"""
if not copy:
# remove all vertices not in the sub_tree
bunch = set(pre_order(self, vtx_id))
for vid in self:
if vid not in bunch:
self.remove_vertex(vid)
self._root = vtx_id
self._parent[self._root] = None
return self
else:
treeid_id = {}
tree = Tree()
tree.root = 0
treeid_id[vtx_id] = tree.root
subtree = pre_order(self, vtx_id)
subtree.next()
for vid in subtree:
parent = treeid_id[self.parent(vid)]
v = tree.add_child(parent)
treeid_id[vid] = v
return tree
def insert_sibling_tree(self, vid, tree ):
"""
Insert a tree before the vid.
vid and the root of the tree are siblings.
Complexity have to be O(1) if tree comes from the actual tree
( tree= self.sub_tree() )
:param vid: vertex identifier
:param tree: a rooted tree
"""
treeid_id = {}
root = tree.root
root_id = self.insert_sibling(vid)
treeid_id[root]=root_id
# pre_order traversal from root and renumbering
for vtx_id in pre_order(tree, vid):
parent = treeid_id[tree.parent(vtx_id)]
v = self.add_child(parent)
treeid_id[vtx_id] = v
return treeid_id
def insert_sibling_tree(self, vid, tree):
"""
Insert a tree before the vid.
vid and the root of the tree are siblings.
Complexity have to be O(1) if tree comes from the actual tree
( tree= self.sub_tree() )
:param vid: vertex identifier
:param tree: a rooted tree
"""
treeid_id = {}
root = tree.root
root_id = self.insert_sibling(vid)
treeid_id[root] = root_id
# pre_order traversal from root and renumbering
for vtx_id in pre_order(tree, vid):
parent = treeid_id[tree.parent(vtx_id)]
v = self.add_child(parent)
treeid_id[vtx_id] = v
return treeid_id
