InfoVis Cyberinfrastructure - Visualizing Tree Data

Description

Many data sets come in tree format. There are family trees, organizational charts, classification hierarchies, and directory structures. The figure below shows an inheritance tree by Ernst Haeckel ((Stammbaum) in German). Read also To Draw a Tree by Pat Hanrahan.

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A tree graph is a set of straight line segments (edges) connected at their ends containing no closed loops (cycles). You can also call it a simple, undirected, connected, acyclic graph (or, equivalently, a connected forest). A tree with n nodes has n-1 graph edges. All trees are bipartite graphs.

Many trees have a root node and are called rooted trees. Trees without a root node are called free trees. Subsequently, we will only consider rooted trees. In rooted trees, all nodes except the root node have only one parent node. Nodes which have no children are called leaf nodes. All other nodes are referred to as intermediate nodes.

Original URL

http://iv.slis.indiana.edu/lm/lm-trees.html

http://iv.slis.indiana.edu/lm/lm-trees.html