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from ete3 import Tree
# Loads a tree. Note that we use format 1 to read internal node names
t = Tree('((((H,K)D,(F,I)G)B,E)A,((L,(N,Q)O)J,(P,S)M)C);', format=1)
print("original tree looks like this:")
# This is an alternative way of using "print t". Thus we have a bit
# more of control on how tree is printed. Here i print the tree
# showing internal node names
print(t.get_ascii(show_internal=True))
#
# /-H
# /D-------|
# | \-K
# /B-------|
# | | /-F
# /A-------| \G-------|
# | | \-I
# | |
# | \-E
#-NoName--|
# | /-L
# | /J-------|
# | | | /-N
# | | \O-------|
# \C-------| \-Q
# |
# | /-P
# \M-------|
# \-S
# Get pointers to specific nodes
G = t.search_nodes(name="G")[0]
J = t.search_nodes(name="J")[0]
C = t.search_nodes(name="C")[0]
# If we remove J from the tree, the whole partition under J node will
# be detached from the tree and it will be considered an independent
# tree. We can do the same thing using two approaches: J.detach() or
# C.remove_child(J)
removed_node = J.detach() # = C.remove_child(J)
# if we know print the original tree, we will see how J partition is
# no longer there.
print("Tree after REMOVING the node J")
print(t.get_ascii(show_internal=True))
# /-H
# /D-------|
# | \-K
# /B-------|
# | | /-F
# /A-------| \G-------|
# | | \-I
# | |
#-NoName--| \-E
# |
# | /-P
# \C------- /M-------|
# \-S
# however, if we DELETE the node G, only G will be eliminated from the
# tree, and all its descendants will then hang from the next upper
# node.
G.delete()
print("Tree after DELETING the node G")
print(t.get_ascii(show_internal=True))
# /-H
# /D-------|
# | \-K
# /B-------|
# | |--F
# /A-------| |
# | | \-I
# | |
#-NoName--| \-E
# |
# | /-P
# \C------- /M-------|
# \-S
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