Design Elements: The Dtree Digital Tree Module The PC samples constitute sparse data and prospect uses a Digital Tree to manage storage and retrieval of the data (code is in prospect/dtree) Also called "trie" from the word "Retrieval" Part of the data is also the index A quaternary trie is used which means there can be four items in each node the trie is 16 levels deep for a 32-bit entity five consecutive values will extend the trie to the maximum level