About

PyBST implements Binary Trees, AVL Trees, Splay Trees, and Red Black Trees in Python. Furthermore, PyBST provides a module for plotting these trees using networkx and matplotlib.

Tree Classes Provided:

• BSTree - represents an unbalanced Binary Search Tree

• AVLTree - represents a balanced AVL Tree

• SplayTree - represents an adjusted Splay Tree

• RBTree - represents a balanced Red Black Tree

Constructor

Let Tree represent one of the provided tree classes mentioned above.

• Tree() - > Creates a new empty tree

• Tree(seq) -> Creates a new empty tree from seq [(key1,val1),(key2,val2),…,(keyn,valn)]

Methods

Tree Methods:

• is_valid() -> Produces True if Tree is a valid tree of its type, else False.

• preorder() -> Produces a sequence of the Nodes in Tree in preorder.

• inorder() -> Produces a sequence of the Nodes in Tree in inorder.

• postorder() -> Produces a sequence of the Nodes in Tree in postorder.

• levelorder() -> Produces a sequence of the Nodes in Tree in levelorder.

• get_node(key) -> Produces the Node in Tree with key attribute key.

• insert(key,val) <==> Tree[key] = value. Inserts a new Node with key attribute key and value attribute val into Tree.

• insert_from(seq) -> Inserts keys and values from seq [(key1,val1),(key2,val2),…,(keyn,valn)] into Tree.

• get_max() <==> max(Tree). Produces the Node with the maximum key in Tree.

• get_min() <==> min(Tree). Produces the Node with the minimum key in Tree.

• get_element_count <==> len(Tree). Produces the number of elements in Tree.

• get_height() -> Produces the height of Tree.

• delete(key) <==> del Tree[key]. Deletes the Node with key attribute key from Tree.

• delete_from(seq) -> Deletes Nodes with keys from seq [key1,key2,…,keyn] from Tree.

Plotting Methods (draw Module):

• plot_tree(Tree) -> Provides a visual representation of Tree via plotting it using networkx and matplotlib.

Dependencies

PyBST requires no external dependencies for the tree classes and their methods themselves. However, note that the following packages are required for tree plotting:

Networkx: http://networkx.github.com/

Matplotlib: http://matplotlib.org/

Installation

From source:

python setup.py install

Using easy install:

easy_install pybst

Alternatively download one of the build distributions found under Downloads.

Documentation

See PyBST’s github repository at: https://github.com/TylerSandman/PyBST/